
<PAGE>
 
                                                                   EXHIBIT 10.22

                    CONSENT AND LOAN MODIFICATION AGREEMENT

     THIS CONSENT AND LOAN MODIFICATION AGREEMENT ("Agreement") is dated as of 
the     day of June, 1997 (the "Effective Date"), by and between THE SUMITOMO
    ---
BANK, LIMITED, a Japanese banking institution acting through its NEW YORK BRANCH
("Lender"), STUART S. LEVIN and GERALD R. PERRAS, either of whom may act 
("Trustee"), SOUTHWEST MARKET LIMITED PARTNERSHIP, a District of Columbia 
limited partnership ("Borrower"), BOSTON PROPERTIES LIMITED PARTNERSHIP, a 
Delaware limited partnership (the "Operating Partnership"), and MORTIMER B. 
ZUCKERMAN and EDWARD H. LINDE (each an "Initial Guarantor" and jointly and 
severally the "Initial Guarantors").

                                   RECITALS:

     WHEREAS, Borrower and Lender are the parties to that certain Construction
Loan Agreement, dated as of August 21, 1990, pursuant to which Lender, in
periodic advances, advanced to Borrower the aggregate principal amount of Eighty
Million and No/100 Dollars ($80,000,000.00) (the "Loan"), as amended by that
certain Loan Modification and Extension Agreement, made as of September 26,
1994, by and among Borrower, Lender, and Initial Guarantors (collectively, the
"Loan Agreement"); and

     WHEREAS, all advances made by Lender to Borrower pursuant to the Loan 
Agreement are evidenced by that certain $80,000,000 Promissory Note made by 
Borrower to the order of Lender and dated as of August 21, 1990, as amended by 
that certain Allonge by and among Borrower and Lender dated as of September 26, 
1994 (collectively, the "Note"); and

     WHEREAS, the Note is secured by, among other things, (i) that certain 
Construction Loan Deed of Trust and Security Agreement dated as of August 18, 
1990, and effective as of August 21, 1990, from Borrower, as trustor, to Trustee
for the benefit of Lender, which was recorded as Instrument Number 46387 among 
the land records of the District of Columbia and encumbering certain real 
property located in the District of Columbia and more particularly described on 
Exhibit A attached hereto and by this reference made a part hereof (the 
- ---------
"Property"), as amended by that certain First Amendment to Construction Loan
Deed of Trust and Security Agreement by and among Borrower, Lender and Trustee,
made as of February 25, 1991, and effective as of August 21, 1990, which was
recorded among the Land Records of the District of Columbia as Instrument Number
12123, as amended by that certain Second Amendment to Construction Loan Deed of
Trust and Security Agreement by and among Borrower, Lender and Trustee, made as
of September 9, 1994, and effective as of September 21, 1994, which was recorded
among the Land Records of the District of Columbia
<PAGE>
 
as Instrument Number 76267, as amended by that certain Third Amendment to
Construction Loan Deed of Trust and Security Agreement by and among Borrower,
Lender and Trustee, made as of September 23, 1994, and effective as of September
26, 1994, which was recorded among the Land Records of the District of Columbia
as Instrument Number 80519 (collectively, the "Deed of Trust"), and (ii) that
certain Collateral Assignment of Leases. Rents, Profits and Income and Pledge of
Accounts dated as of August 18, 1990, and effective as of August 21, 1990, by
Borrower to Lender which was recorded among the Land Records of the District of
Columbia as Instrument Number 46388, as amended by that certain First Amendment
to Collateral Assignment of Leases, Rents, Profits and Income and Pledge of
Accounts made as of February 22, 1991, and effective as of August 21, 1990, by
and among Borrower and Lender, which was recorded among the Land Records of the
District of Columbia as Instrument Number 12124, as amended by that certain
Second Amendment to Collateral Assignment of Leases, Rents, Profits and Income
and Pledge of Accounts made as of September 23, 1994, and effective as of
September 26, 1994, by and among Borrower and Lender, which was recorded among
the Land Records of the District of Columbia as Instrument Number 80518
(collectively, the "Assignment of Rents"); and 

        WHEREAS, in connection with the Loan the Initial Guarantors executed and
delivered to Lender that certain Interest Guaranty and Indemnity dated August
21, 1990, as amended by that certain First Amendment to Interest Guaranty and
Indemnity made as of September 26, 1994 by and among Lender and Initial
Guarantors, as amended herein (collectively, the "Interest Guaranty"); and

        WHEREAS, in connection with the Loan the Initial Guarantors executed
and delivered to Lender that certain Environmental Guaranty dated August 21,
1990 (the "Environmental Guaranty" and, together with the Interest Guaranty,
the "Initial Guarantees"); and

        WHEREAS, Borrower is a District of Columbia limited partnership, and its
sole general partner is Boston Southwest Associates Limited Partnership, a 
Massachusetts limited partnership ("BSALP"), and the general partner of BSALP is
Independence Square, Inc., a Delaware corporation ("ISI"), and the shareholders 
of ISI are Mortimer B. Zuckerman and Edward H. Linde; and

        WHEREAS, concurrently herewith, an initial public offering (the "IPO") 
of shares in Boston Properties, Inc., a Delaware corporation (the "REIT") is 
taking place in accordance with the S-11 registration statement as filed with 
the Securities and Exchange Commission as a "red herring" on May 27, 1997 and 
made effective prior to the date hereof by the Securities and Exchange 
Commission; and

        WHEREAS, the REIT is the sole general partner of the Operating 
Partnership; and
<PAGE>
 
        WHEREAS, the REIT and the Operating Partnership collectively own 100% of
the membership interests in Boston Properties LLC, a Delaware limited liability 
company ("BP LLC"); and

        WHEREAS, the REIT, the Operating Partnership and BP LLC were formed to 
succeed to the real estate business of the Borrower and other companies founded 
by the Initial Guarantors; and

        WHEREAS, concurrently herewith, the following partnership transfers are 
taking place: (i) a one percent (1%) general partnership interest in Borrower is
being transferred to BP LLC, and (ii) the Operating Partnership is succeeding to
(x) the remaining sixty-nine percent (69%) general partnership interest in 
Borrower which is being converted into a sixty-nine percent (69%) limited 
partnership interest in Borrower, and (y) the remaining thirty percent (30%) 
limited partnership interest in Borrower; and

        WHEREAS, in connection with such partnership transfers the Operating 
Partnership has agreed to execute new guaranty agreements in accordance with the
terms and conditions set forth below.

        NOW, THEREFORE, in consideration of the premises contained herein and 
other good and valuable consideration, the receipt and sufficiency of which are 
hereby acknowledged, Borrower, Lender, Initial Guarantors and Operating 
Partnership hereby agree as follows:

        1. The foregoing recitals are incorporated into this Agreement for all 
purposes by this reference.

        2. Notwithstanding anything to the contrary contained in the Loan 
Agreement, Deed of Trust, Assignment of Rents, Note, Initial Guarantees or any 
other instruments evidencing or securing the Loan (collectively, the "Loan 
Documents"), Lender hereby consents (i) to the transfer and assignment by BSALP
of a one percent (1%) general partnership interest in Borrower to BP LLC, and
(ii) to the Operating Partnership succeeding to a sixty-nine percent (69%)
general partnership interest in Borrower which is simultaneously being converted
into a sixty-nine percent (69%) limited partnership interest in Borrower, and
(iii) to the Operating Partnership succeeding to the remaining thirty percent
(30%) limited partnership interest in Borrower, and (iv) to BP LLC becoming the
sole general partner of Borrower with a one percent (1%) partnership interest,
and (v) to the Operating Partnership becoming the limited partner of Borrower
with a ninety-nine percent (99%) partnership interest. Lender acknowledges and
agrees that any and all conditions to such consent, whether contained in the
Loan Documents, or otherwise, have been satisfied.
<PAGE>
 
        3. Notwithstanding the provisions of Section 7.22 of the Loan Agreement 
or Section 1.20 of the Deed of Trust, or anything else to the contrary contained
in any of the Loan Documents, Lender hereby acknowledges and agrees, that 
without any notice to or consent by Lender, any person or entity may engage from
time to time in transfers of stock, membership, partnership or other equity 
interests in BP LLC, the Operating Partnership, the REIT, or any of their 
respective direct or indirect owners; provided, however, that any such transfer 
does not result in the occurrence of any of the following: (i) the REIT ceases 
to be the sole general partner of the Operating Partnership or ceases to own at 
least a five percent (5%) interest in the Operating Partnership, (ii) the 
Operating Partnership ceases to be the sole managing member of BP LLC, a 
Delaware limited liability company, (iii) the Operating Partnership ceases to 
own a controlling interest (which, in any event, must not be less than a 51% 
ownership interest) in BP LLC, or (iv) BP LLC ceases to be the sole general 
partner of Borrower or ceases to own at least a one percent (1%) interest in 
Borrower.

        4. From and after the Effective Date, all references contained in the 
Loan Documents to the general partner of Borrower shall be deemed to refer to BP
LLC (and its permitted assigns) and not to BSALP OR ISI.

        5. The Operating Partnership agrees to execute and deliver to Lender a 
new Interest Guaranty in the form attached hereto as Exhibit B (the "New 
                                                     ---------
Interest Guaranty") and a new Environmental Guaranty in the form attached
hereto as Exhibit C (the "New Environmental Guaranty"). From and after the
          ---------
Effective Date, wherever the terms "Interest Guaranty," "Environmental Guaranty"
and "Guarantors" are used in the Deed of Trust, Loan Agreement or any other Loan
Documents, they shall be deemed to include, in addition to such original 
documents, the New Interest Guaranty, New Environmental Guaranty and Operating 
Partnership, respectively.

        6. The Interest Guaranty is hereby amended to delete the following 
clause from Section 1.1:

                ", during any month in which (a) the Debt Service Coverage Ratio
                of the Premises is less than 1.05, or (b) any Person, through
                any agreement with, action of, or cooperation by any Guarantor,
                Borrower or any Affiliate of Borrower has obtained an interest
                in Rents payable pursuant to Government Leases (as those terms
                are defined in the Assignment of Rents) which then is or
                thereafter becomes (other than with Lender's express written
                consent) superior to Lender's interest in such Rents"

Further, the Interest Guaranty is hereby amended to add the following sentence 
at the end of Section 8 thereof:

                "If either Guarantor fails to deliver such financial statement 
                within 120 days next following the end of his fiscal year, such 
                Guarantor agrees to pay to Lender, for himself but not for the 
                other Guarantor, a fee in the
 






<PAGE>
 
          amount of $500.00 per day, commencing 30 days after written notice
          from Lender that such Guarantor failed to deliver to Lender such
          financial statement and continuing until such financial statement is
          delivered to Lender."

     7.  Except as set forth in Section 6 above and except as expressly modified
below, Initial Guarantors hereby absolutely, unconditionally and fully reaffirm 
all of their guarantees, obligations and agreements under the Initial Guarantees
according to the terms thereof and agree to the provisions of this Agreement. 
The Initial Guarantees shall continue in full force and effect, however, subject
to the last sentence of this paragraph, it is understood and agreed that (i) the
breach or failure to perform any representation, warranty or covenant under any 
Loan Documents, other than the Initial Guarantees, by or about the Initial 
Guarantors, or (ii) the occurrence of any event to or with respect to the 
Initial Guarantors, shall not, by itself, constitute a breach, default or Event 
of Default under any Loan Document, other than the Initial Guarantees. By way of
example and not as a limitation on the foregoing, from and after the Effective 
Date (a) the filing of claims, litigation or judgments against any of the 
Initial Guarantors, (b) the institution of any bankruptcy, reorganization or 
insolvency proceedings by or against any of the Initial Guarantors, or the 
appointment of a receiver or a similar official for any of the properties of any
of the Initial Guarantors (or the occurrence of any other events with respect to
the Initial Guarantors referenced in Section 2.01(k) of the Deed of Trust), and
(c) the failure to comply with any requirements regarding the delivery of
certificates, financial statements and other financial information, tax returns
or any other documentation or information or notices relating to the Initial
Guarantors, shall not constitute a breach, default or Event of Default under any
Loan Document, other than the Initial Guarantees. The foregoing provisions of
this Section 7 shall in no way limit; (x) the liability or obligations of the
Initial Guarantors under the Interest Guaranty or the Environmental Guaranty, or
(y) the right of Lender to enforce all remedies directly against any of the
Initial Guarantors for failure to pay or perform the Obligations, or (z) the
liability of the Operating Partnership under the New Interest Guaranty and New
Environmental Guaranty.

     8.  Lender has previously approved the Management Agreement (the 
"Management Agreement") by and between Borrower and Boston Properties, Inc. a 
Massachusetts corporation (the "Manager"), dated as of May 1, 1991. Lender 
hereby consents to the assignment of Manager's interest in the Management 
Agreement to the Operating Partnership and the Operating Partnership's 
assumption of the same. Following such assignment, the Operating Partnership 
agrees (i) to attorn to Lender in the event that Lender takes possession or 
assumes control of the Property, and (ii) that if an Event of Default shall have
occurred under the terms of the Loan Agreement, any payment of the management 
fee pursuant to the terms of the Management Agreement after the Event of Default
shall have occurred shall be subordinate to the repayment of the Loan in 
accordance with the terms of the Loan Agreement. Lender hereby approves (in 
accordance with Section 7.16 of the Loan Agreement and Sections 1.16 and 1.18 of
the Deed of Trust) the engagement of the Operating Partnership to serve as the 
manager of the Property in accordance with the Management Agreement.

                                      -5-
<PAGE>
 
     9.  Lender hereby approves the form of the Amended and Restated Agreement 
of Limited Partnership of Borrower and the Certificate of Amendment of Limited 
Partnership delivered to Lender herewith and consents to the restatement of the 
partnership agreement for Borrower in accordance therewith.

    10.  Section 7.30(b) of the Loan Agreement is hereby amended by deleting the
word "quarterly" and inserting, in lieu thereof, the word "monthly." Lender 
agrees that, provided there is no uncured Event of Default under any of the Loan
Documents, Borrower may make daily or periodic "sweeps" of its operating 
accounts into a master operating account maintained by the REIT and/or the 
Operating Partnership.

    11.  The Operating Partnership covenants and agrees to provide Lender with 
copies of the (i) audited balance sheets and statements of income, changes in 
stockholders' equity, and cash flow for the REIT as of and for each fiscal year 
as set forth in the REIT's annual report of form 10-K, and (ii) unaudited 
balance sheets and statements of income, changes in stockholders' equity, and 
cash flow for the REIT as of and for each calendar quarter as set forth in the 
REIT's quarterly report on form 10-Q, and (iii) promptly upon their becoming 
available, copies of any registration statements and any amendments and 
supplements thereto, and any regular and periodic reports, if any, filed by the 
REIT with the Securities and Exchange Commission or any governmental authority 
succeeding to any or all of the functions of the said Commission.

    12.  Borrower warrants and represents to Lender that (a) the financial 
statements incorporated in the S-11 registration statement of the REIT as filed 
and made effective by the Securities and Exchange Commission heretofore 
delivered to Lender are true and correct in all material respects and from the 
date of such financial statements to the date hereof there has been no material 
adverse change in the financial condition of the Operating Partnership that 
would impair its ability to perform its obligations under this Agreement or the
New Interest Guaranty or the New Environmental Guaranty, and (b) the IPO and the
formation of the REIT, the Operating Partnership and BP LLC have been completed 
and the structure set forth in the recitals to this Agreement are true and 
correct.

    13.  The Operating Partnership hereby represents and warrants to Lender as 
follows: (i) the Operating Partnership is a limited partnership, duly organized,
validly existing and in good standing under the laws of the State of Delaware; 
(ii) the Operating Partnership has the authority, rights and franchises to own 
its properties, to carry on its business as now conducted, to perform its 
obligations under this Agreement, and has made all filings in each jurisdiction 
in which the character of its business or nature of its properties makes such 
filings necessary and where not filing could have a material adverse impact on 
its business; (iii) the Operating Partnership has the authority and legal right 
to execute, deliver and perform this Agreement and has taken all necessary 
partnership action to authorize the execution, delivery and performance of this 
Agreement; (iv) no consent, license, permit, approval or authorization of, 
exemption by, notice or report to, or registration, filing or declaration with 
any court, governmental authority, or third party which has not been obtained is
required for the execution, delivery and performance by the Operating
Partnership of this Agreement; (v) this

                                      -6-

<PAGE>
 
Agreement has been executed and delivered by the Operating Partnership and 
constitutes (and on the Effective Date of this Agreement will constitute) the 
legal, valid and binding obligation of the Operating Partnership, enforceable 
against the Operating Partnership in accordance with its terms:  and (vi) 
neither the execution not delivery of this Agreement nor the fulfillment of or 
compliance with the terms and provisions hereof, nor the consummation of the 
transactions contemplated hereby will conflict with or result in a breach of the
terms, conditions or provisions of, or constitute a default under, or result in 
any violation of its partnership agreement, any other contract, any award of any
arbitrator or any agreement, instrument, order or judgment or regulation or law 
to which the Operating Partnership is subject, or to or by which it or its 
properties or its assets are bound or affected.

        14.  The Borrower hereby represents and warrants to Lender as follows:  
(i) the Borrower is a limited partnership, duly organized, validly existing and 
in good standing under the laws of the District of Colombia; (ii) the Borrower 
has the authority, rights and franchises to own its properties, to carry on its 
business as now conducted, to perform its obligations under this Agreement, and 
has made all filings in each jurisdiction in which the character of its business
or nature of its properties makes such filings necessary and where not filing 
could have a material adverse impact on its business; (iii) the Borrower has the
authority and legal right to execute, deliver and perform this Agreement and has
taken all necessary partnership action to authorize the execution, delivery and 
performance of this Agreement; (iv) no consent, license, permit, approval or 
authorization of, exemption by, notice or report to, or registration, filing or 
declaration with any court, governmental authority, or third party which has not
been obtained is required for the execution, delivery and performance by the 
Borrower of this Agreement; (v) this Agreement has been executed and delivered 
by the Borrower and constitutes (and, on the Effective Date of this Agreement 
will constitute) the legal, valid and binding obligation of the Borrower, 
enforceable against the Borrower in accordance with its terms; and (vi) neither 
the execution nor delivery of this Agreement nor the fulfillment of or 
compliance with the terms and provisions hereof, nor the consummation of the 
transactions contemplated hereby will conflict with or result in a breach of the
terms, conditions or provisions of, or constitute a default under, or result in 
any violation of its partnership agreement, any other contract, any award of any
arbitrator or any agreement, instrument, order or judgment or regulation or law
to which the Borrower is subject, or to or by which it or its properties or its
assets are bound or affected.

        15.  Except as expressly modified above, the Loan Documents are hereby 
ratified and confirmed by Borrower and shall continue in full force and effect. 
Borrower and Initial Guarantors acknowledge and agree that as of the Effective 
Date there exist no offsets, defenses, counterclaims, or abatements to their 
respective obligations under the Loan Documents as modified herein, and, to the 
knowledge of Borrower and Initial Guarantors, all obligations of Lender 
thereunder have been fully performed.

        16.  Lender hereby represents and warrants as follows:  (i) the 
outstanding principal balance of the Loan as of June 1, 1997 is $78,125,000,
(ii) to Lender's actual knowledge, the Loan is not in default, and (iii) it has 
received all necessary and appropriate authorizations to enter into and perform 
this Agreement.

                                      -7-
<PAGE>
 
     17.  Nothing contained herein shall constitute, or be deemed to constitute,
any limitation on the validity or enforceability or priority of the Note, the
Deed of Trust or any other Loan Documents as amended hereby nor shall this 
Agreement be deemed to create any interest different from that created by the
Deed of Trust, which interest continues unimpaired and in full force and effect 
in accordance with the terms of the Deed of Trust.  The parties hereto further 
acknowledge and agree that the "Limitation on Resource" provisions of the Loan 
Documents (Section 3.21 of the Deed of Trust, Section 9.21 of the Loan 
Agreement, Section 11 of the Note and Section 5.15 of the Assignment of Rents) 
shall continue in full force and effect.

     18.  Borrower agrees to pay all out-of-pocket expenses incurred by Lender 
in connection with the transaction set forth above, including reasonable legal 
fees and expenses.

     19.  This Agreement may be executed in counterparts, each of which shall be
deemed an original, but all of which, taken together, shall constitute one and 
the same document.  This Agreement shall be governed by and construed in 
accordance with the laws of the District of Columbia.  As evidenced by its 
execution hereof, Lender authorizes and directs Trustee to join herein.

     IN WITNESS WHEREOF, Southwest Market Limited Partnership has caused these 
presents to be signed in its partnership name by Boston Properties LLC, its 
general partner, which in turn has caused these presents to be signed in its 
partnership name by Boston Properties Limited Partnership, its managing member, 
which in turn has caused these presents to be signed in its partnership name by 
Boston Properties, Inc., its general partner, as of the day and year first above
written, and for the purposes thereof, Boston Properties, Inc. has caused these 
presents to be signed in its corporate name by Edward H. Linde, its president,

                                      -8-
<PAGE>
 

attested by ___________________, its ___________________, and its corporate seal
to be affixed hereto, and does hereby constitute and appoint Edward H. Linde as 
its true and lawful attorney-in-fact for it and in its name to acknowledge and 
deliver this instrument as the act and deed of such corporation and partnership.





                                        LENDER:
ATTEST:

                                        THE SUMITOMO BANK, LIMITED,
                                         a Japanese banking institution acting
                                         through its NEW YORK BRANCH



                                        By:    
- ---------------------------------          -----------------------------------

                                        Name:  
                                             ---------------------------------

                                        Title: 
                                              --------------------------------

                      [Signatures Continued On Next Page]

                                      -9-
<PAGE>
                         
                               BORROWER:
                        
ATTEST:                 
                        
                               SOUTHWEST MARKET LIMITED
                                PARTNERSHIP, a District of Columbia
                                limited partnership
                        
                               By:  BOSTON PROPERTIES LLC,
                                     a Delaware limited liability company, 
                                     its General Partner


                                    By:  BOSTON PROPERTIES
                                          LIMITED PARTNERSHIP,
                                          a Delaware limited partnership,
                                          its Managing Member

                                         By:  BOSTON PROPERTIES,
                                               INC., a Delaware corporation


                                              By:  /s/ Edward H. Linde
- ----------------------------                       ---------------------------
                                                   Edward H. Linde
                                                   President


                      [SIGNATURES CONTINUED ON NEXT PAGE]

                                     -10-
<PAGE>
 
                                   OPERATING PARTNERSHIP:                
ATTEST:                                                                  
                                                                         
                                   BOSTON PROPERTIES LIMITED             
                                    PARTNERSHIP, a Delaware limited      
                                    partnership                          
                                                                         
                                   By:  BOSTON PROPERTIES, INC.,         
                                         a Delaware corporation          
                                                                         
                                                                         
                                        By:  /s/ Edward H. Linde        
- -------------------------                    --------------------------- 
                                             Edward H. Linde            
                                             President                  
                                                                         
                                                                         
                                   TRUSTEE:                              
                                                                         
                                                                         
                                   ------------------------------------- 
                                               , sole acting trustee     
                                                                         
                                                                         
                                   INITIAL GUARANTORS:                   
                                                                         
                                                                         
                                                                         
                                   ------------------------------------- 
                                   Mortimer B. Zuckerman                 
                                                                         
                                                                         
                                   /s/ Edward H. Linde               
                                   ------------------------------------- 
                                   Edward H. Linde                        
                                       
                                       
                                     -11-
