<PAGE>
 
                                                                   EXHIBIT 10.35


              CONSENT OF BANKS AND FIRST AMENDMENT TO AMENDED AND
                      RESTATED REVOLVING CREDIT AGREEMENT


     This Consent of Banks and First Amendment to Amended and Restated Revolving
Credit Agreement, is effective the 4th day of April, 1997, and is made and
entered into by and among HALTER MARINE GROUP, INC., a Delaware corporation
("Borrower") and the undersigned Banks, including Whitney National Bank in its
capacity as a Bank and as Agent for the Banks under the Amended and Restated
Revolving Credit Agreement (which is hereinafter described).

     WHEREAS, the parties hereto entered into an Amended and Restated Revolving
Credit Agreement, effective December 31, 1996 (the "Revolving Credit
Agreement");

     WHEREAS, the parties hereto desire to amend the Revolving Credit Agreement;

     WHEREAS, Borrower has requested the Banks to consent to Borrower obtaining
a Loan for the acquisition of an interest in additional Subsidiaries and the
Banks are willing to consent thereto subject to the provisions hereof; and

     WHEREAS, Borrower intends to approach the Banks in the future about the
incurrence of a Loan or other Indebtedness in order to purchase the balance of
the outstanding capital stock of such Subsidiaries but Borrower recognizes that
further consents of the Required Banks are required in order for Borrower to
incur any such Loan or other Indebtedness and/or to purchase such additional
stock.

     NOW THEREFORE, for good and adequate consideration the receipt of which is
hereby acknowledged, the parties hereto do hereby agree as follows:

     1.  As used herein, capitalized terms not defined herein shall have the
meanings attributed to them in the Revolving Credit Agreement.

     2.  The Banks do hereby consent to the purchase by Halter Marine, Inc.
("Halter-Nevada"), a Nevada Corporation and wholly owned Subsidiary of Borrower,
and consent to the use of Nineteen Million Three Hundred Seventy-Two Thousand
Five Hundred Dollars ($19,372,500.00) in Loan proceeds (the "$19,372,500.00
Loan") obtained by Borrower for the purchase of (a) Fifty-One Thousand (51,000)
shares of capital stock of Maritime Holdings, Inc.("MHI"), a Delaware
Corporation, for the price and sum of Fifteen Million Four Hundred Ninety-Eight
Thousand Dollars ($15,498,000.00) and (b) One Hundred Two (102) shares of the
capital stock of Texas Drydock, Inc. ("TDI"), a Texas Corporation, for the price
and sum of Three Million Eight Hundred Seventy-Four Thousand Five Hundred
Dollars ($3,874,500.00) (collectively, the "MHI and Texas Drydock Acquisition").

     3.  The consent of the Banks to the MHI and Texas Drydock Acquisition is
subject to Borrower paying and Borrower agrees to pay, within three (3) months
after the effective date of this Consent of Banks and First Amendment to Amended
and Restated Revolving Credit Agreement, the $19,372,500.00 Loan incurred for
the MHI and Texas Drydock Acquisition through the incurrence of a future Loan or
other Indebtedness (in each case, in accordance with the terms of the Revolving
Credit Agreement).  Borrower acknowledges and agrees that the further consent of
the Required Banks is required in order for Borrower to incur any such future
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Loan or other Indebtedness described in this Paragraph 3 which consent shall not
be unreasonably withheld.

     4.  The parties hereto do hereby amend and restate the definition of
"Company Business" in the Revolving Credit Agreement to read as follows:

     Company Business shall mean (i) the construction, repair and conversion of
     ocean-going and inland vessels, (ii) the construction, repair and
     conversion of drilling rigs, barges and vessels, (iii) the production of
     any component of or accessory to any such ocean-going or inland vessel or
     drilling rig, barge or vessel, (iv) any other similar type of production,
     construction or manufacturing, (v) any financing related to the sale of any
     of the Borrower's or any Subsidiary's products, and (vi) any other
     activities ancillary to the foregoing.

     5.   The parties hereto do hereby amend and restate the definition of
"Subsidiary" in the Revolving Credit Agreement to read as follows:

     Subsidiary shall mean (a) any corporation of which more than fifty percent
     (50%) of the issued and outstanding capital stock entitled to vote for the
     election of directors (other than by reason of default in the payment of
     dividends) is at the time owned directly or indirectly by Borrower and/or
     any one or more Subsidiary of Borrower, or (b) any partnership, limited
     liability company, business trust, or any other similar entity of which
     more than fifty percent (50%) of the voting interests is at the time owned
     directly or indirectly by Borrower and/or any one or more Subsidiary of
     Borrower, and specifically including, but not limited to, each of the
     entities described on Schedule 7.8 hereto.

     6.   The parties hereto do hereby amend and restate Section 7.8 of the
Revolving Credit Agreement to read as follows:

     7.8  Subsidiaries.  There are no Subsidiaries other than as identified on
     Schedule 7.8 attached hereto, as the same may from time to time be amended,
     modified or supplemented as provided herein.  The capital stock of each
     Subsidiary is duly authorized, validly issued and fully paid and
     nonassessable and, except for Maritime Holdings, Inc. and Texas Drydock,
     Inc., is owned solely by Borrower and/or any one or more Subsidiaries.
     Except as disclosed on Schedule 7.8 attached hereto, neither Borrower nor
     any of its Subsidiaries, individually or collectively, owns or holds,
     directly or indirectly, any capital stock or equity security of, or any
     equity interest in, any corporation or business.  Borrower may at any time
     amend, modify or supplement Schedule 7.8 by notifying the Agent in writing
     of any changes thereto, including any formation, acquisition, merger or
     liquidation of Subsidiaries or any change in the capitalization of any
     Subsidiary, in each case, in accordance with the terms of this Agreement
     and provided that any such new Subsidiary shall, within thirty (30) days of
     the creation or acquisition of such Subsidiary, execute and deliver to
     Agent for the benefit of all the Banks a Continuing Guarantee in form of
     Exhibit C annexed hereto and made a part hereof.

     7.   Notwithstanding Sections 7.8 and 8.1(p) of the Revolving Credit
Agreement and the definition of "Continuing Guarantee" in the Revolving Credit
Agreement, MHI, TDI, and

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TDI International, Ltd. ("TDI International"), a Cayman Islands corporation,
shall not be required to execute a Continuing Guarantee unless and until MHI or
TDI become wholly owned Subsidiaries of Borrower and/or any one or more
Subsidiaries.

     8.   Advances or loans from Borrower and/or any one or more Subsidiaries to
MHI, TDI and/or TDI International shall not be considered a Restricted
Investment so long as (a) such advances and loans are represented by a
promissory note, (b) such advances and loans do not in the aggregate at any one
time exceed the MHI Borrowing Base and (c) the advances and loans to TDI
International do not in the aggregate at any one time exceed Five Million
Dollars ($5,000,000.00).  The "MHI Borrowing Base" shall mean the sum of Thirty
Million Dollars ($30,000,000.00) less the sum of (a) the aggregate amount of all
loans and advances outstanding from Borrower and/or any one or more Subsidiaries
to MHI, TDI and/or TDI International (including principal, interest and any
fees) plus (b) the aggregate principal amount of all outstanding Letter of
Credit Loans arising out of Letter(s) of Credit securing or guaranteeing
obligations of or performance by MHI, TDI and/or TDI International plus (c) the
aggregate undrawn face amount of all outstanding Letter(s) of Credit securing or
guaranteeing obligations of or performance by MHI, TDI and/or TDI International.

     9.   The parties hereto do hereby amend Section 4.1(a) of the Revolving
Credit Agreement to add the following additional restrictions regarding the
issuance of Letters of Credit:

     (viii)  the sum of (A) the aggregate undrawn face amount of all outstanding
             Letter(s) of Credit securing or guaranteeing obligations of or
             performance by MHI, TDI and/or TDI International plus (B) the
             aggregate principal amount of all outstanding Letter of Credit
             Loans arising out of Letter(s) of Credit securing or guaranteeing
             obligations of or performance by MHI, TDI and/or TDI International
             shall not at any one time exceed the sum of Thirty Million Dollars
             ($30,000,000.00); and

     (ix)    the sum of (A) the aggregate undrawn face amount of all outstanding
             Letter(s) of Credit securing or guaranteeing obligations of or
             performance by TDI International plus (B) the aggregate principal
             amount of all outstanding Letter of Credit Loans arising out of
             Letter(s) of Credit securing or guaranteeing obligations of or
             performance by TDI International shall not at any one time exceed
             the sum of Five Million Dollars ($5,000,000.00).

     10.  The parties hereto do hereby amend and restate Section 4.1(a)(vii) of
the Revolving Credit Agreement to read as follows:

     (vii)   the sum of (A) the aggregate undrawn face amount of all outstanding
             Letter(s) of Credit securing or guaranteeing obligations of or
             performance by Offshore plus (B) the aggregate principal amount of
             all outstanding Letter of Credit Loans arising out of Letter(s) of
             Credit securing or guaranteeing obligations of or performance by
             Offshore shall not at any one time exceed the Offshore Commitment.

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     11.  Within ten (10) of the effective date hereof Borrower shall furnish
Agent with the following:

     (a)  A Stock Pledge Agreement (the "Stock Pledge Agreement") by Halter-
          Nevada whereby Halter-Nevada grants Agent for the benefit of the Banks
          a first pledge and security interest in the stock of MHI and TDI owned
          by Halter-Nevada, which Stock Pledge Agreement shall be in such form
          as Agent may reasonably require;

     (b)  Such resolutions and certificates of  Halter-Nevada and its officers
          and such opinions of McGlinchey Stafford, a Professional Limited
          Liability Company, or other counsel acceptable to Agent, relating to
          the execution, delivery and performance by Halter-Nevada of the Stock
          Pledge Agreement and the perfection and priority of the security
          interest created thereby as may be required by Agent and satisfactory
          in form and substance to the Agent;

     (c)  Such resolutions and certificates of Borrower and its officers
          relating to the execution, delivery and performance by Borrower of
          this Consent of Banks and First Amendment to Amended and Restated
          Revolving Credit Agreement as may be required by Agent and
          satisfactory in form and substance to the Agent; and

     (d)  An agreement by the Subsidiaries which executed Continuing Guarantees
          in such form as Agent may require consenting to the execution of this
          Consent of Banks and First Amendment to Amended and Restated Revolving
          Credit Agreement together with such resolutions and certificates of
          such Subsidiaries and its officers relating thereto as may be required
          by Agent and satisfactory in form and substance to the Agent.

     12.  An amended and restated Schedule 7.8 to the Revolving Credit Agreement
is annexed hereto.

     13.  An amended and restated Schedule 7.12 to the Revolving Credit
Agreement is annexed hereto.

     14.  In connection with the foregoing and only in connection with the
foregoing, the Revolving Credit Agreement is hereby amended, but in all other
respects all of the terms, conditions and provisions of the Revolving Credit
Agreement remain unaffected.

     15.  This Consent of Banks and First Amendment to Amended and Restated
Revolving Credit Agreement may be executed in two or more counterparts, and it
shall not be necessary that the signatures of all parties hereto be contained on
any one counterpart hereof; each counterpart shall be deemed an original, but
all of which together shall constitute one and the same instrument.


                  TO THE END OF PAGE INTENTIONALLY LEFT BLANK
                                        

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<PAGE>



 
  IN WITNESS WHEREOF, the parties hereto have caused this instrument to be duly
executed.

HALTER MARINE GROUP, INC.


BY:    /s/ KEITH L. VOIGTS
       _______________________________
ITS:   Senior Vice President - Finance
       _______________________________
13085 Seaway Road
Gulfport, MS 39503
Telecopy number: (601) 897-4888


WHITNEY NATIONAL BANK

 
BY:    /s/ SIGNATURE APPEARS HERE
       _______________________________
ITS:   Assistant Vice President
       _______________________________
228 St. Charles Avenue
New Orleans, LA 70130
Telecopy number: (504) 552-4622


FIRST NATIONAL BANK OF COMMERCE


BY:    /s/ JOHN C. CUMMING
       _______________________________
ITS:   Assistant Vice President
       _______________________________
Energy Services Dept., 2nd Fl.
210 Baronne Street
New Orleans, LA 70112
Telecopy number: (504) 561-1316


HIBERNIA NATIONAL BANK


BY:    /s/ SIGNATURE APPEARS HERE
       _______________________________
ITS:   Vice President
       _______________________________
313 Carondelet Street
New Orleans, LA 70130
Telecopy number: (504) 533-5434



THE FIRST NATIONAL BANK OF CHICAGO


BY:    /s/ CORY M. OLSON
       _______________________________
ITS:   Vice President
       _______________________________
One First National Plaza
Suite 0324
10th Floor
Chicago, IL 60670
Telecopy number: (312) 732-3055


THE BANK OF NOVA SCOTIA


BY:    /s/ V. C. H. ASHBY
       _______________________________
ITS:   Senior Manager Loan Operations
       _______________________________
600 Peachtree Street NE
Suite 2700
Atlanta, GA 30308
Telecopy number: (404) 888-8998


BANK ONE, LOUISIANA, N.A.


BY:    /s/ LYNN RICHARD
       _______________________________
ITS:   Vice President
       _______________________________
201 St. Charles Avenue
Suite 1410
New Orleans, LA 70170
Telecopy number: (504) 558-1279


THE BANK OF TOKYO--MITSUBISHI, LTD.


BY:    _________________________
ITS:   _________________________
2001 Ross Avenue, LB118
3150 Trammel Crow Center
Dallas, TX 75201
Telecopy number: (214) 954-1007

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                                 Schedule 7.8

                             List of Subsidiaries


1.   Halter Marine, Inc. (a Nevada corporation)
2.   Equitable Shipyards, Inc.
3.   Gretna Machine and Iron Works, Inc.
4.   Gulf Coast Fabrication, Inc.
5.   Halter Marine, Inc. (a Louisiana corporation)
6.   Halter Marine Services, Inc.
7.   Halter Marine Gulf Repair, Inc.
8.   Halter Marine Gulfport, Inc.
9.   Halter Marine Panama City, Inc.
10.  Halter Marine Pascagoula, Inc.
11.  Trinity Yachts, Inc.
12.  Washington Marine Fabricators, Inc.
13.  Offshore Marine Indemnity Company
14.  Maritime Holdings, Inc.
15.  Texas Drydock, Inc.
16.  TDI International, Ltd.

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