<PAGE>
                                                                   EXHIBIT 10.12

                                                                  EXECUTION COPY


                  AMENDMENT AND WAIVER dated as of June 27, 2002 (this
            "Amendment"), to the Credit Agreement dated as of May 14, 1999, as
            amended (the "Credit Agreement"), among ALASKA COMMUNICATIONS
            SYSTEMS GROUP, INC., a Delaware corporation ("Holdings"), ALASKA
            COMMUNICATIONS SYSTEMS HOLDINGS, INC., a Delaware corporation (the
            "Borrower"), the lenders party thereto, JPMORGAN CHASE BANK
            (formerly known as THE CHASE MANHATTAN BANK), a New York banking
            corporation, as Administrative Agent, CANADIAN IMPERIAL BANK OF
            COMMERCE, as Syndication Agent, and CREDIT SUISSE FIRST BOSTON
            CORPORATION, as Documentation Agent.

            A. The Lenders have extended credit to the Borrower, and have agreed
to extend credit to the Borrower, in each case pursuant to the terms and subject
to the conditions set forth in the Credit Agreement.

            B. Holdings and the Borrower have requested that the Required
Lenders amend and waive certain provisions of the Credit Agreement as set forth
herein.

            C. The Required Lenders are willing so to amend and waive the Credit
Agreement pursuant to the terms and subject to the conditions set forth herein.

            D. Capitalized terms used but not defined herein have the meanings
assigned to them in the Credit Agreement.

            Accordingly, in consideration of the mutual agreements herein
contained and other good and valuable consideration, the sufficiency and receipt
of which are hereby acknowledged, the parties hereto agree as follows:

            SECTION 1. Waiver. The Required Lenders hereby waive compliance with
Sections 6.04 and 6.08 of the Credit Agreement to the extent necessary to permit
(a) any purchases by Holdings on or after the date on which this Amendment
becomes effective of common Equity Interests issued by Holdings and (b) the
payment of dividends or the making of any loans or other transfers by the
Borrower to Holdings on or after the date on which this Amendment becomes
effective to the extent necessary to provide Holdings with the funds necessary
to effect any such purchases, provided that (i) the aggregate consideration,
fees and expenses paid by Holdings in connection with such purchases shall not
exceed $15,000,000, (ii) no Default shall exist at the time of any such purchase
and (iii) all such purchases shall be made using existing cash of Holdings, the
Borrower or any Subsidiary.

            SECTION 2. Amendments. Section 6.08(b) of the Credit Agreement is
hereby amended by:

            (a) replacing the period at the end of clause (v) thereof with the
text "; and" and

            (b) inserting the following text after clause (v) thereof:

            "(vi) payment to any Person of Indebtedness of the Borrower or any
Subsidiary (other than a License Subsidiary) that is incurred to finance the
purchase of equipment or other fixed assets and is secured by such equipment or
other fixed assets, provided that (A) the aggregate amount of all payments made
pursuant to this clause (vi) does not exceed (1) $2,500,000 during any fiscal
year of the Borrower and (2) $5,000,000 during the term of this Agreement and
(B) all such payments shall be made using existing cash of the Borrower or any
Subsidiary (other than a License Subsidiary)."

<PAGE>

            SECTION 3. Representations and Warranties. Each of Holdings and the
Borrower represents and warrants to the Administrative Agent and to each of the
Lenders that:

            (a) This Amendment has been duly authorized, executed and delivered
by each of Holdings and the Borrower and constitutes a legal, valid and binding
obligation of Holdings and the Borrower, enforceable in accordance with its
terms, subject to applicable bankruptcy, insolvency, reorganization, moratorium
or other laws affecting creditors' rights generally and subject to general
principles of equity, regardless of whether considered in a proceeding in equity
or at law.

            (b) The representations and warranties of Holdings and the Borrower
set forth in the Loan Documents are true and correct on and as of the date
hereof, except to the extent such representations and warranties expressly
relate to an earlier date, in which case such representations and warranties are
true and correct as of such earlier date.

            (c) Immediately after giving effect to this Amendment, no Default
shall have occurred and be continuing.

            SECTION 4. Conditions to Effectiveness. This Amendment shall become
effective as of the date first above written when the Administrative Agent shall
have received (a) counterparts of this Amendment that, when taken together, bear
the signatures of (i) Holdings, (ii) the Borrower and (iii) the Required Lenders
and (b) the amendment fees required to be paid by the Borrower pursuant to
Section 6 hereof, provided that the representations and warranties set forth in
the Loan Documents are true and correct as of the date that the last of such
counterparts is received, except to the extent such representations and
warranties expressly relate to an earlier date.

            SECTION 5. Credit Agreement. Except as specifically amended and
waived hereby, the Credit Agreement shall continue in full force and effect in
accordance with the provisions thereof as in existence on the date hereof. After
the date hereof, any reference to the Credit Agreement shall mean the Credit
Agreement as amended and waived hereby. This Amendment shall be a Loan Document
for all purposes.

            SECTION 6. Amendment Fee. In consideration of the agreements of the
Lenders contained in this Amendment, the Borrower agrees to pay promptly to the
Administrative Agent, for the account of each Lender that delivers an executed
counterpart of this Amendment at or prior to 5:00 p.m., New York time, on June
27, 2002, an amendment fee in an amount equal to 0.05% of the sum of such
Lender's Revolving Commitment and outstanding Term Loans, provided that such fee
shall not be payable unless and until all conditions to the effectiveness of
this Amendment as provided in Section 4 hereof (other than payment of such
amendment fee) shall have been satisfied.

            SECTION 7. APPLICABLE LAW. THIS AMENDMENT SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE STATE OF NEW YORK.

            SECTION 8. Counterparts. This Amendment may be executed in two or
more counterparts, each of which shall constitute an original but all of which
when taken together shall constitute but one agreement. Delivery of an executed
signature page to this Amendment by facsimile transmission shall be effective as
delivery of a manually signed counterpart of this Amendment.

            SECTION 9. Expenses. The Borrower agrees to reimburse the
Administrative Agent for its out-of-pocket expenses in connection with this
Amendment, including the reasonable fees, charges and disbursements of Cravath,
Swaine & Moore, counsel for the Administrative Agent.

<PAGE>

            IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed by their respective authorized officers as of the day and year
first written above.



                                        ALASKA COMMUNICATIONS SYSTEMS GROUP,
                                         INC.,

                                           by  /s/    Kevin P. Hemenway
                                               ---------------------------------
                                               Name:  Kevin P. Hemenway
                                               Title: Senior Vice President,
                                                      Chief Financial Officer
                                                      and Treasurer

                                        ALASKA COMMUNICATIONS SYSTEMS HOLDINGS,
                                        INC.,

                                           by  /s/    Kevin P. Hemenway
                                               ---------------------------------
                                               Name:  Kevin P. Hemenway
                                               Title: Senior Vice President,
                                                      Chief Financial Officer
                                                      and Treasurer


                                        JPMORGAN CHASE BANK (formerly
                                           known as THE CHASE MANHATTAN
                                           BANK), individually and as
                                           Administrative Agent,

                                           by  /s/    John Kowalczuk
                                               ---------------------------------
                                               Name:  John Kowalczuk
                                               Title: Vice President


                                        CANADIAN IMPERIAL BANK OF COMMERCE,
                                           as Syndication Agent,

                                           by  /s/    Joan S. Griffin
                                               ---------------------------------
                                               Name:  Joan S. Griffin
                                               Title: Executive Director


                                        CREDIT SUISSE FIRST BOSTON CORPORATION,
                                           individually and as Documentation
                                           Agent,

                                           by  /s/    Paul J. Corona
                                               ---------------------------------
                                               Name:  Paul J. Corona
                                               Title: Director

                                           by  /s/    Bill O'Daly
                                               ---------------------------------
                                               Name:  Bill O'Daly
                                               Title: Director

<PAGE>
                                                               SIGNATURE PAGE TO
                                                            AMENDMENT AND WAIVER
                                                                     DATED AS OF
                                                                   JUNE 27, 2002

TO APPROVE THE AMENDMENT:

Name of Institution:                    Allstate Life Insurance Company

                                        By: /s/    Jerry D. Zinkula
                                            ------------------------------------
                                            Name:  Jerry D. Zinkula
                                            Title: Authorized Signatory

                                        By: /s/    Patricia W. Wilson
                                            ------------------------------------
                                            Name:  Patricia W. Wilson
                                            Title: Authorized Signatory

Name of Institution:                    ARES Leveraged  Investment Fund II, L.P
                                        By: ARES Management II, L.P
                                            General Partner

                                        By: /s/ Jeff Moore
                                            ------------------------------------
                                            Name:  Jeff Moore
                                            Title:    Vice President

Name of Institution:                    ARES III CLO Ltd.
                                        By: ARES CLO Management LLC

                                        By: /s/    Jeff Moore
                                            ------------------------------------
                                            Name:  Jeff Moore
                                            Title: Vice President

Name of Institution:                    ARES IV CLO Ltd.

                                        By: ARES CLO Management IV, LP,
                                            Investment Manager

                                        By: ARES CLO GP IV, LLC,
                                            Its Managing Member

                                        By: /s/    Jeff Moore
                                            ------------------------------------
                                            Name:  Jeff Moore
                                            Title: Vice President

Name of Institution:                    ARES V CLO Ltd.

                                        By: ARES CLO Management V, LP,
                                            Investment Manager

                                        By: ARES CLO GP V, LLC,
                                            Its Managing Member

                                        By: /s/    Jeff Moore
                                            ------------------------------------
                                            Name:  Jeff Moore
                                            Title: Vice President

<PAGE>
Name of Institution:                    ARES VI CLO Ltd.

                                        By: ARES Management VI, L.P.
                                            Investment Manager

                                        By: ARES CLO GP VI, LLC,
                                            Its Managing Member

                                        By: /s/    Jeff Moore
                                            ------------------------------------
                                            Name:  Jeff Moore
                                            Title: Vice President

Name of Institution:                    Capitva II Finance Ltd.

                                        by  /s/    David Dyer
                                            ------------------------------------
                                            Name:  David Dyer
                                            Title: Director

Name of Institution:                    CoBank, ACB

                                        by  /s/    Aaron Dyer
                                            ------------------------------------
                                            Name:  Aaron Dyer
                                            Title: Assistant Vice President

Name of Institution:                    C-Squared CDO Ltd.
                                        By: TCW Advisors Inc., as its
                                            Portfolio Manager

                                        by  /s/    Mark L. Gold
                                            ------------------------------------
                                            Name:  Mark L. Gold
                                            Title: Managing Director

Name of Institution:                    ELC (Cayman) Ltd. 1999-II
                                        By: David L. Babson & Company Inc.
                                            as Collateral Manager

                                        by  /s/    Adrienne Musgnug
                                            ------------------------------------
                                            Name:  Adrienne Musgnug
                                            Title: Managing Director

Name of Institution:                    ELC (Cayman) Ltd. CDO Series 1999-I
                                        By: David L. Babson & Company Inc.
                                            as Collateral Manager

                                        by  /s/    Adrienne Musgnug
                                            ------------------------------------
                                            Name:  Adrienne Musgnug
                                            Title: Managing Director

Name of Institution:                    Franklin Floating Rate Trust

                                        by  /s/    Richard D'Addario
                                            ------------------------------------
                                            Name:  Richard D'Addario
                                            Title: Vice President

<PAGE>
Name of Institution:                    Gallatin Funding I Ltd.

                                        By: Bear Stearns Asset Management Inc.
                                            as its Collateral Manager

                                        by  /s/    Justin Driscoll
                                            ------------------------------------
                                            Name:  Justin Driscoll
                                            Title: Managing Director

Name of Institution:                    Grayston CLO 2002-01 Ltd.

                                        By: Bear Stearns Asset Management Inc.
                                            as its Collateral Manager

                                        by  /s/    Justin Driscoll
                                            ------------------------------------
                                            Name:  Justin Driscoll
                                            Title: Managing Director

Name of Institution:                    KZH Crescent LLC

                                        by  /s/    Joyce Fraser-Bryant
                                            ------------------------------------
                                            Name:  Joyce Fraser-Bryant
                                            Title: Authorized Agent

Name of Institution:                    KZH Crescent 2 LLC

                                        by  /s/    Joyce Fraser-Bryant
                                            ------------------------------------
                                            Name:  Joyce Fraser-Bryant
                                            Title: Authorized Agent

Name of Institution:                    KZH Crescent 3 LLC

                                        by  /s/    Joyce Fraser-Bryant
                                            ------------------------------------
                                            Name:  Joyce Fraser-Bryant
                                            Title: Authorized Agent

Name of Institution:                    National City Bank

                                        by  /s/    David Denlinger
                                            ------------------------------------
                                            Name:  David Denlinger
                                            Title: Assistant Vice President

Name of Institution:                    National Cooperative Services
                                        Corporation

                                        by  /s/    Kenneth A. Fried
                                            ------------------------------------
                                            Name:  Kenneth A. Fried
                                            Title: Associate Vice President

<PAGE>

Name of Institution:                    Sequils I, Ltd

                                        By: TCW Advisors Inc., as its
                                            Collateral Manager

                                        by  /s/    Mark L. Gold
                                            ------------------------------------
                                            Name:  Mark L. Gold
                                            Title: Managing Director

                                        by  /s/    William Brennan
                                            ------------------------------------
                                            Name:  William Brennan
                                            Title: Vice President

Name of Institution:                    Sequils IV, Ltd

                                        By: TCW Advisors Inc., as its
                                            Collateral Manager

                                        by  /s/    Mark L. Gold
                                            ------------------------------------
                                            Name:  Mark L. Gold
                                            Title: Managing Director

                                        by  /s/    William Brennan
                                            ------------------------------------
                                            Name:  William Brennan
                                            Title: Vice President

Name of Institution:                    TCW Leveraged Income Trust IV, L.P.
                                        By: TCW (LINC IV), L.L.C.,
                                            As General Partner

                                        By: TCW Asset Management Company
                                            As managing member of the
                                            General Partner

                                        by  /s/    Mark L. Gold
                                            ------------------------------------
                                            Name:  Mark L. Gold
                                            Title: Managing Director

                                        by  /s/    William Brennan
                                            ------------------------------------
                                            Name:  William Brennan
                                            Title: Vice President

Name of Institution:                    TCW Select Loan Fund, Limited
                                        By: TCW Advisors Inc., as its
                                            Collateral Manager

                                        by  /s/    Mark L. Gold
                                            ------------------------------------
                                            Name:  Mark L. Gold
                                            Title: Managing Director

                                        by  /s/    William Brennan
                                            ------------------------------------
                                            Name:  William Brennan
                                            Title: Vice President

<PAGE>

Name of Institution:                    United of Omaha Life Insurance Company
                                        By: TCW Asset Management Company,
                                            Its Investment Advisor

                                        by  /s/    Mark L. Gold
                                            ------------------------------------
                                            Name:  Mark L. Gold
                                            Title: Managing Director

                                        by  /s/    William Brennan
                                            ------------------------------------
                                            Name:  William Brennan
                                            Title: Vice President

Name of Institution:                    U.S. Bank National Association

                                        by  /s/    Thomas G. Gunder
                                            ------------------------------------
                                            Name:  Thomas G. Gunder
                                            Title: Vice President

Name of Institution:                    Webster Bank

                                        by  /s/    Elisabeth V. Piker
                                            ------------------------------------
                                            Name:  Elisabeth V. Piker
                                            Title: Vice President

Name of Institution:                    Wells Fargo Bank Alaska, N.A.

                                        by  /s/    Anthony Alvarado
                                            ------------------------------------
                                            Name:  Anthony Alvarado
                                            Title: Vice President