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                                                                     EXHIBIT 5.1


                    [Letterhead of Appleby Spurling & Kempe]


                                                              6th September 2002


Nabors Industries Ltd.
c/o The Corporate Secretary Limited
Whitepark House
White Park Road
Bridgetown, Barbados

Dear Sirs

NABORS INDUSTRIES LTD. (THE "COMPANY")

We have acted as legal counsel to the Company in Bermuda and this opinion is
addressed to you in connection with the filing by the Company with the
Securities and Exchange Commission under the Securities Act of 1933, as amended,
of a Registration Statement on Form S-3 on 6th September 2002, in relation to
the registration of up to 1,000,000 common shares of par value US$0.001 each
(the "Shares") in the share capital of the Company (the "Registration
Statement").

For the purposes of this opinion we have examined and relied upon the documents
listed, and in some cases defined, in the Schedule to this opinion (the
"Documents").

ASSUMPTIONS

In stating our opinion we have assumed:-

(a)      the authenticity, accuracy and completeness of all Documents submitted
         to us, and such other documents examined by us, as originals, and the
         conformity to authentic original Documents of all Documents submitted
         to us, and such other documents examined by us, as certified,
         conformed, notarised, faxed or photostatic copies;

(b)      that each of the Documents and other such documentation which was
         received by electronic means is complete, intact and in conformity with
         the transmission as sent;

(c)      the genuineness of all signatures on the Documents;

(d)      the authority, capacity and power of each of the persons signing the
         Documents (other than the Company);

(e)      that any representation, warranty or statement of fact or law, other
         than as to the laws of Bermuda, made in any of the Documents is true,
         accurate and complete;

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Nabors Industries Ltd.                  2                       6 September 2002


(f)      that there are no provisions of the laws or regulations of any
         jurisdiction other than Bermuda which would be contravened by the
         execution or delivery of the Subject Agreements or the Registration
         Statement or which would have any implication in relation to the
         opinion expressed herein and that, in so far as any obligation under,
         or action to be taken under, the Registration Statement or the Subject
         Agreements is required to be performed or taken in any jurisdiction
         outside Bermuda such action or obligation will not be illegal by virtue
         of the laws of that jurisdiction;

(g)      that each of the Company or any other party to the Subject Agreements
         is not carrying on investment business in or from within Bermuda under
         the provisions of the Investment Business Act 1998 as amended from time
         to time;

(h)      that the records which were the subject of the Company Search were
         complete and accurate at the time of such search and disclosed all
         information which is material for the purposes of this opinion and such
         information has not since the date of the Company Search been
         materially altered;

(i)      that the records which were the subject of the Litigation Search were
         complete and accurate at the time of such search and disclosed all
         information which is material for the purposes of this opinion and such
         information has not since the date of the Litigation Search been
         materially altered;

(j)      that the Resolutions are in full force and effect, have not been
         rescinded, either in whole or in part, and there is no matter affecting
         the authority of the Directors to enter into the Subject Agreements, or
         to perform their obligations under the Registration Statement not
         disclosed by the Constitutional Documents or the Resolutions, which
         would have any adverse implication in relation to the opinions
         expressed herein;

(k)      that the Subject Agreements will effect and constitute legal, valid and
         binding obligations of the parties thereto, enforceable in accordance
         with its terms under the laws of the Province of Alberta by which they
         are expressed to be governed and that the Company has entered into its
         obligations under the Subject Agreements in good faith for the purpose
         of carrying on its business and that, at the time it did so, there were
         reasonable grounds for believing that the transactions contemplated by
         the Subject Agreements would benefit the Company;

(l)      that the Subject Agreements constitutes the legal, valid and binding
         obligations of the parties thereto, other than the Company, under the
         laws of their jurisdiction of incorporation or jurisdiction of
         formation;

(m)      that the Subject Agreements have been validly authorised, executed and
         delivered by each of the parties thereto, other than the Company, and
         the

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Nabors Industries Ltd.                  3                       6 September 2002


         performance thereof is within the capacity and power of each such party
         thereto and that each such party to which the Company purportedly
         delivered the Subject Agreements has actually received and accepted
         delivery of the Subject Agreements; and

(n)      that as a consequence of the Subject Agreements, the Company will
         receive money or monies worth at least equal to the value of the Shares
         being issued and none of such Shares will be issued for less than the
         par value thereof.

OPINION

Based upon and subject to the foregoing and subject to the reservations set out
below and to any matters not disclosed to us, we are of the opinion that:-

(1)      The Company is an exempted company incorporated with limited liability
         and existing under the laws of Bermuda. The Company possesses the
         capacity to sue and be sued in its own name and is in good standing
         under the laws of Bermuda.

(2)      The Company has taken all necessary corporate action to authorise the
         delivery of the Registration Statement and the registration of the
         Shares pursuant to the Registration Statement.

(3)      The Company has taken all necessary corporate action to authorise the
         issuance of the Shares.

(4)      When issued in accordance with the Resolutions and the Subject
         Agreements, the Shares will be duly and validly issued, fully paid,
         non-assessable shares of the Company.

(5)      The issue by the Company of the Shares will not violate:-

         (a)      any provision of any applicable law of Bermuda, nor, as far as
                  can be ascertained from public record, any regulation or order
                  of any governmental, judicial or public body or authority of
                  or in Bermuda;

         (b)      the Memorandum of Association or Bye-laws of the Company.

(6)      Other than obtaining the consent of the Bermuda Monetary Authority to
         the issue and transfer of the Shares, which consent has been obtained
         there is no registration or filing with, or consent, license, approval,
         declaration, permission, authorisation, exemption or similar instrument
         of, or the taking of any other action by any person in Bermuda which is
         required in connection with the issuance of the Shares.

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Nabors Industries Ltd.                  4                       6 September 2002


(7)      Based solely upon the Company Search and the Litigation Search:

         (i)      no litigation, arbitration or administrative or other
                  proceeding of or before any arbitrator or governmental
                  authority of Bermuda is pending against or affecting the
                  Company or against or affecting any of its properties, rights,
                  revenues or assets; and

         (ii)     no notice to the Registrar of Companies of the passing of a
                  resolution of members or creditors to wind up or the
                  appointment of a liquidator or receiver has been given. No
                  petition to wind up the Company or application to reorganise
                  its affairs pursuant to a Scheme of Arrangement or application
                  for the appointment of a receiver has been filed with the
                  Supreme Court.

(8)      The Company has received an assurance from the Ministry of Finance
         granting an exemption, until 28 March 2016, from the imposition of tax
         under any applicable Bermuda law computed on profits or income or
         computed on any capital asset, gain or appreciation, or any tax in the
         nature of estate duty or inheritance tax, provided that such exemption
         shall not prevent the application of any such tax or duty to such
         persons as are ordinarily resident in Bermuda and shall not prevent the
         application of any tax payable in accordance with the provisions of the
         Land Tax Act 1967 or otherwise payable in relation to land in Bermuda
         leased to the Company. There are, subject as otherwise provided in this
         opinion, no Bermuda taxes, stamp or documentary taxes, duties or
         similar charges now due, or which could in the future become due, in
         connection with the delivery, performance of the Subject Agreements or
         the transactions contemplated thereby and the Company is not required
         by any Bermuda law or regulation to make any deductions or withholdings
         in Bermuda from any payment it may make thereunder.

RESERVATIONS

We have the following reservations:-

(a)      The term "enforceable" as used in this opinion means that there is a
         way of ensuring that each party performs an agreement or that there are
         remedies available for breach.

(b)      We express no opinion as to the availability of equitable remedies such
         as specific performance or injunctive relief, or as to any matters,
         which are within the discretion of the courts of Bermuda in respect of
         any obligations of the Company as set out in the Subject Agreements. In
         particular, we express no opinion as to the enforceability of any
         present or future waiver of any provision of law (whether substantive
         or procedural) or of any right or remedy which might otherwise be
         available presently or in the future under the Subject Agreements.

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Nabors Industries Ltd.                  5                       6 September 2002


(c)      Enforcement of the obligations of the Company under the Subject
         Agreements may be limited or affected by applicable laws from time to
         time in effect relating to bankruptcy, insolvency or liquidation or any
         other laws or other legal procedures affecting generally the
         enforcement of creditors' rights.

(d)      Enforcement of the obligations of the Company may be the subject of a
         statutory limitation of the time within which such proceedings may be
         brought.

(e)      We express no opinion as to any law other than Bermuda law and none of
         the opinions expressed herein relates to compliance with or matters
         governed by the laws of any jurisdiction except Bermuda. This opinion
         is limited to Bermuda law as applied by the Courts of Bermuda at the
         date hereof.

(f)      Where an obligation is to be performed in a jurisdiction other than
         Bermuda, the courts of Bermuda may refuse to enforce it to the extent
         that such performance would be illegal under the laws of, or contrary
         to public policy of, such other jurisdiction.

(g)      Where a person is vested with a discretion or may determine a matter in
         his or its opinion, such discretion may have to be exercised reasonably
         or such an opinion may have to be based on reasonable grounds.

(h)      A Bermuda court may refuse to give effect to any provisions of the
         Subject Agreements in respect of costs of unsuccessful litigation
         brought before the Bermuda court or where that court has itself made an
         order for costs.

(i)      Searches of the Register of Companies at the office of the Registrar of
         Companies and of the Supreme Court Causes Book at the Registry of the
         Supreme Court are not conclusive and it should be noted that the
         Register of Companies and the Supreme Court Causes Book do not reveal:

         (i)      whether an application to the Supreme Court for a winding up
                  petition or for the appointment of a receiver or manager has
                  been prepared but not yet been presented or has been presented
                  but does not appear in the Causes Book at the date and time
                  the Search is concluded;

         (ii)     whether any arbitration or administrative proceedings are
                  pending or whether any proceedings are threatened, or whether
                  any arbitrator has been appointed;

         (iii)    details of matters which have been lodged for filing or
                  registration which as a matter of general practice of the
                  Registrar of Companies would have or should have been
                  disclosed on the public file but have not actually been
                  registered or to the extent that they have been registered
                  have not been disclosed or do not appear in the public records
                  at the date and time the search is concluded;

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Nabors Industries Ltd.                  6                       6 September 2002


         (iv)     details of matters which should have been lodged for
                  registration but have not been lodged for registration at the
                  date the search is concluded; or

         (v)      whether a receiver or manager has been appointed privately
                  pursuant to the provisions of a debenture or other security,
                  unless notice of the fact has been entered in the Register of
                  Charges in accordance with the provisions of the Companies Act
                  1981.

         Furthermore, in the absence of a statutorily defined system for the
         registration of charges created by companies incorporated outside
         Bermuda ("overseas companies") over their assets located in Bermuda, it
         is not possible to determine definitively from searches of the Register
         of Charges maintained by the Registrar of Companies in respect of such
         overseas companies what charges have been registered over any of their
         assets located in Bermuda or whether any one charge has priority over
         any other charge over such assets.

(j)      In order to issue this opinion we have carried out the Company Search
         as referred to in the Schedule to this opinion and have not enquired as
         to whether there has been any change since the date and time such
         search was completed.

(k)      In order to issue this opinion we have carried out the Litigation
         Search as referred to in the Schedule to this opinion and have not
         enquired as to whether there has been any change since the date and
         time such search was completed.

(l)      In paragraph (1) above, the term "good standing" means that the Company
         has received a Certificate of Compliance from the Registrar of
         Companies.

(m)      Any reference to this opinion to being "non-assessable" shall mean to
         fully-paid shares of the Company and subject to any contrary provision
         in any agreement in writing between the Company and the holder of
         shares, that no shareholder shall be obliged to contribute further
         amounts to the capital of the Company, either in order to complete
         payment for their shares, to satisfy claims of creditors of the
         Company, or otherwise; and no shareholder shall be bound by an
         alteration of the Memorandum of Association or Bye-laws of the Company
         after the date on which he became a shareholder, if and so far as the
         alteration requires him to take, or subscribe for additional shares, or
         in any way increase his liability to contribute to the share capital
         of, or otherwise to pay money to the Company.

DISCLOSURE

This opinion is addressed to you solely for your benefit and is neither to be
transmitted to any other person, nor relied upon by any other person or for any
other purpose nor quoted or referred to in any public document nor filed with
any governmental agency or

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Nabors Industries Ltd.                  7                       6 September 2002


person, without our prior written consent. We consent to the filing of this
opinion as an exhibit to the Registration Statement.

This opinion speaks as of its date and is strictly limited to the matters stated
herein and we assume no obligation to review or update this opinion if
applicable law or the existing facts or circumstances should change.

Yours faithfully

/s/ APPLEBY SPURLING & KEMPE


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                                    SCHEDULE


1.       The entries and filings shown in respect of the Company on the file of
         the Company maintained in the Register of Companies at office of the
         Registrar of Companies in Hamilton, Bermuda, as revealed by a search
         completed on 3rd September, 2002 (the "Company Search").

2.       The entries and filings shown in respect of the Company in the Supreme
         Court Causes Book maintained at the Registry of the Supreme Court in
         Hamilton, Bermuda, as revealed by a search completed on 3rd September,
         2002 in respect of the Company (the "Litigation Search").

         (The Company Search and the Litigation Search are together referred to
         as the "Searches").

3.       A copy of the final Registration Statement on Form S-3, pursuant to
         which the Company will register 1,000,000 common shares of par value
         US$0.001 each in the share capital of the Company.

4.       Certified copies of the Certificate of Incorporation, Memorandum of
         Association and Bye-laws for the Company (collectively referred to as
         the "Constitutional Documents").

5.       A certified copy of the minutes of the Board of Directors of the
         Company effective 17th July, 2002 and copies of the minutes of the
         Board of Director's meeting held 24th June 2002 (the "Resolutions").

6.       A certified copy of the "Foreign Exchange Letter", dated 11 December,
         2001 and a letter of permission dated 15 April 2002, issued by the
         Bermuda Monetary Authority, Hamilton Bermuda in relation to the
         Company.

7.       A certified copy of the "Tax Assurance", dated 7 January, 2002, issued
         by the Registrar of Companies for the Minister of Finance in relation
         to the Company.

8.       A Certificate of Compliance, dated 3rd September, 2002 issued by the
         Ministry of Finance in respect of the Company.

9.       A copy of the executed Support Agreement dated as of 26 April, 2002,
         between the Nabors Industries, Inc., Nabors ExchangeCo (Canada) Inc.
         and 3064297 Novia Scotia Company (the "Support Agreement").

10.      A copy of the executed Voting and Exchange Trust Agreement dated as of
         26 April, 2002, between Nabors Industries, Inc., Nabors ExchangeCo
         (Canada) Inc.

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         and Computershare Trust Company of Canada (the "Voting and Exchange
         Trust Agreement").

11.      An executed copy of the Acknowledgement of Novation of the Support
         Agreement and the Voting and Exchange Trust Agreement executed by the
         Company, and addressed to Nabors Industries, Inc., Nabors ExchangeCo
         (Canada) Inc. and Computershare Trust Company of Canada (the
         "Acknowledgement of Novation").

12.      An executed copy of the Arrangement Agreement dated 12 August 2002
         entered into between the Company and Ryan Energy Technologies Inc. (the
         "Arrangement Agreement").

         The Support Agreement, the Voting and Exchange Trust Agreement, the
         Acknowledgement of Novation and the Arrangement Agreement are
         collectively referred to in this opinion as the "Subject Agreements".

