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                                                                   EXHIBIT 24.13

                               POWER OF ATTORNEY

                  FILING OF REGISTRATION STATEMENT ON FORM S-4

     KNOW ALL MEN BY THESE PRESENTS, that the undersigned director and/or
officer of Northrop Grumman Corporation a Delaware corporation and NNG, Inc. a
Delaware corporation (both herein singly and collectively and singly, the
"Corporation") hereby nominates and appoints RICHARD B. WAUGH, JR., W. BURKS
TERRY and JOHN H. MULLAN, and each of them acting or signing singly, his or her
agents and attorneys-in-fact (the "Agents"), in his or her name to execute
and/or file (1) a registration statement on Form S-4 under the Securities Act of
1933, as amended, (the "Act"), in connection with the registration, offer and
sale or exchange under the Act of shares of Common Stock of the Corporation in
connection with the Corporation's tender or exchange offer (including any
associated merger transaction) for the Common Stock, $1.00 par value per share
and Series B $2.00 Cumulative Preferred Stock, $5.00 par value per share of
Litton Industries, Inc.; and (2) any one or more amendments to any part of the
foregoing registration statement, including any post-effective amendments or
appendices or supplements that may be required to be filed under the Act to keep
such registration statement effective or to terminate its effectiveness.

     Further, the undersigned does hereby authorize and direct the said agents
and attorneys-in-fact to take any and all actions and execute and file any and
all documents with the Securities and Exchange Commission (the "SEC"), or state
regulatory agencies, necessary, proper or convenient in their opinion to comply
with the Act and the rules and regulations or orders of the SEC, or state
regulatory agencies, adopted or issued pursuant thereto, including the making of
any requests for acceleration of the effective date of said registration
statement, to the end that the registration statement of the Corporation shall
become effective under the Act and any other applicable law.

     Finally, the undersigned does hereby ratify, confirm and approve each and
every act and document which the said appointed agents and attorneys-in-fact may
take, execute or file pursuant thereto with the same force and effect as though
such action had been taken or such documents had been executed or filed by the
undersigned respectively.

     This Power of Attorney shall remain in full force and effect until revoked
or superseded by written notice filed with the SEC.

     IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney on
the 31st day of January 2001.

                                            Richard J. Stegemeier


                                            /s/ RICHARD J. STEGEMEIER
                                            --------------------------------
                                            Director
