Document:

<PAGE>

                                                                    Exhibit 10-B

                                Amendment No. 5

                                      to

                        National Steel Credit Agreement

          Amendment No. 5 (this "Amendment"), dated as of May 14, 2001, by and
among National Steel Corporation (the "Borrower"), the financial institutions
parties hereto (the "Consenting Lenders"), Citicorp USA, Inc., as agent for the
Lenders and Issuers under the Credit Agreement defined below (the
"Administrative Agent"), and The Fuji Bank, Limited, as syndication agent for
the Lenders and Issuers under the Credit Agreement (defined below) (the
"Syndication Agent"), to that certain Credit Agreement dated as of November 19,
1999 by and among the Borrower, the Administrative Agent, the Syndication Agent
and the financial institutions and other entities from time to time party
thereto as a Lender or Issuer (such Credit Agreement, as heretofore amended, the
"Credit Agreement").

                             W i t n e s s e t h:

          Whereas, the Borrower, the Consenting Lenders, the Administrative
Agent and the Syndication Agent are parties to the Credit Agreement and, as of
the date hereof, the Consenting Lenders constitute Requisite Lenders; and

          Whereas, the parties hereto wish to amend the terms of the Credit
Agreement as set forth herein;

          Now, Therefore, in consideration of the foregoing, the mutual
covenants and obligations herein set forth and other good and valuable
consideration, the adequacy and receipt of which is hereby acknowledged, and in
reliance upon the representations, warranties and covenants herein contained,
the parties hereto, intending to be legally bound, hereby agree as follows:

     Section 1.  Defined Terms. Capitalized terms used herein but not defined
herein shall have the definitions given to them in the Credit Agreement.

     Section 2.  Amendments.

          The Credit Agreement is, effective as of the Amendment Effective Date,
amended as follows:

          (a)  Amendment to Article I (Definitions, Interpretation and
               Accounting Terms)

               (1)  A definition of "Granite City Assets" is hereby inserted in
Section 1.1 (Defined Terms) of the Agreement immediately prior to the definition
of "Gross Receivables Availability" to read in its entirety as follows:
<PAGE>

                                             AMENDMENT NO. 5 TO CREDIT AGREEMENT
                                                      NATIONAL STEEL CORPORATION

               "Granite City Assets" means the "Equipment," "Inventory,"
     "Trademarks" and "Other Assets," each as defined in Schedule V (Granite
     City Assets), having an aggregate Fair Market Value for all such assets not
     in excess of $3,000,000.

          (b)  Amendment to Article VIII (Negative Covenants).

               (1)  Clause (a) of Section 8.7 (Sale of Assets) of the Credit
Agreement is hereby amended and restated in its entirety to read as follows:

               (a)  The Borrower will not, and will not permit any of its
     Material Subsidiaries to, engage in any Asset Sale, except, (i) the sale of
     Accounts and certain related property pursuant to the Receivables Purchase
     Facility to the extent permitted under the Intercreditor Agreement, (ii)
     any Asset Sale permitted under Section 4.08 (Limitation on Sale of
     Mortgaged Property) or (other than an Asset Sale involving any Collateral)
     Section 4.10 (Limitation on Sale of Assets Other than Mortgaged Property)
     of the Indenture, (iii) [Intentionally Omitted], (iv) [Intentionally
     Omitted] and (v) as long as no Default or Event of Default is continuing or
     would result therefrom, the sale of the Granite City Assets for Fair Market
     Value, payable in cash upon such sale; provided, however, that with respect
     to such sale of Granite City Assets, (x) the aggregate consideration
     received for such sale shall not exceed $3,000,000 and (y) all Net Cash
     Proceeds of such sale, other than Net Cash Proceeds from the sale of
     "Equipment" set forth on and as defined in Schedule V (Granite City
     Assets), are applied to the prepayment of the Obligations to the extent
     required by Section 2.9 (Mandatory Prepayments).

          (c)  Amendment to Schedules.

               (1)  A new Schedule V (Granite City Assets) is hereby added to
the Credit Agreement to read in its entirety as set forth in Exhibit A hereto.

     Section 3. Conditions of Effectiveness. This Amendment No. 5 shall become
effective when, and only when, each of the following conditions shall have been
satisfied or duly waived by the Administrative Agent (the "Amendment Effective
Date"):

          (a)  Certain Documents. The Administrative Agent shall have received
all of the following, all of which shall be in form and substance satisfactory
to the Administrative Agent, in sufficient executed copies for each of the
Lenders:

               (1)  this Amendment, duly executed by the Borrower, the
Guarantor, the Administrative Agent and Lenders constituting the Requisite
Lenders;

               (2)  an amendment to the NUF Credit Agreement, duly executed and
delivered by the parties thereto, in form and substance satisfactory to the
Administrative Agent;

               (3)  the "Equipment," as defined Exhibit A hereto, shall be
released from the lien under the Indenture in accordance with its terms, in form
and substance satisfactory to the Administrative Agent;

                                      -2-
<PAGE>

                                             AMENDMENT NO. 5 TO CREDIT AGREEMENT
                                                      NATIONAL STEEL CORPORATION

               (4)  a favorable opinion of Yukevich, Marchetti, Liekar &
Zangrilli, P.C., counsel to the Loan Parties, in form and substance satisfactory
to the Administrative Agent; and

               (5)  such additional documentation as the Administrative Agent or
the Requisite Lenders may reasonably require.

          (b)  Representations and Warranties. Each of the representations and
warranties contained in Article IV (Representations and Warranties) of the
Credit Agreement, the other Loan Documents or in any certificate, document or
financial or other statement furnished at any time under or in connection
therewith are true and correct in all material respects on and as of the
Amendment Effective Date as if made on and as of such date, except to the extent
that such representations and warranties specifically relate to a specific date,
in which case such representations and warranties shall be true and correct in
all material respects as of such specific date; provided, however, that
references therein to the "Credit Agreement" shall be deemed to include this
Amendment;

          (c)  Corporate and Other Proceedings. All corporate and other
proceedings, and all documents, instruments and other legal matters in
connection with the transactions contemplated by this Amendment shall be
satisfactory in all respects in form and substance to the Administrative Agent
and the Requisite Lenders.

          (d)  No Event of Default. No Event of Default or Default shall have
occurred and be continuing on the Amendment Effective Date.

          (e)  Fees and Expenses Paid. On the Amendment Effective Date the
Borrower shall have paid all reasonable costs and expenses of the Administrative
Agent in connection with the preparation, reproduction, execution and delivery
of this Amendment and all other Loan Documents entered into in connection
herewith, including the reasonable fees and out-of-pocket expenses of counsel
for the Administrative Agent with respect thereto and all other Loan Documents
and payment of all costs, expenses and fees due under any Loan Document.

     Section 4.  Representations and Warranties. On and as of the Amendment
Effective Date, after giving effect to this Amendment No. 5, the Borrower hereby
represents and warrants to the Administrative Agent and each Lender as follows:

          (a)  This Amendment has been duly authorized, executed and delivered
by the Borrower and constitutes a legal, valid and binding obligation of the
Borrower, enforceable against the Borrower in accordance with its terms;

          (b)  Neither this Amendment nor the consummation of the transactions
contemplated hereunder constitute a breach of the Indenture or the Receivables
Purchase Facility;

          (c)  Each of the representations and warranties set forth in Article
IV (Representations and Warranties) of the Credit Agreement, the other Loan
Documents or in any certificate, document or financial or other statement
furnished at any time under or in connection therewith are true and correct in
all material respects on and as of the Amendment

                                      -3-
<PAGE>

                                             AMENDMENT NO. 5 TO CREDIT AGREEMENT
                                                      NATIONAL STEEL CORPORATION

Effective Date, except to the extent that such representations and warranties
specifically relate to a specific date, in which case the representations and
warranties shall be true and correct in all material respects as of such
specific date; provided, however, that references therein to the "Credit
Agreement" shall be deemed to include this Amendment; and

          (d)  No Default or Event of Default has occurred and is continuing.

     Section 5.  Reference to the Effect on the Loan Documents.

          (a)  As of the Amendment Effective Date, on and after the date hereof,
each reference in the Credit Agreement to "this Agreement," "hereunder,"
"hereof," "herein," or words of like import, and each reference in the other
Loan Documents to the Credit Agreement, shall mean and be a reference to the
Credit Agreement as amended hereby, and this Amendment and the Credit Agreement
shall be read together and construed as a single instrument. The table of
contents, signature pages and list of Exhibits and Schedules of the Credit
Agreement shall be modified to reflect the changes made in this Amendment.

          (b)  Except as specifically amended herein, the Credit Agreement and
all other Loan Documents shall remain in full force and effect and are hereby
ratified and confirmed.

          (c)  The execution, delivery and effectiveness of this Amendment No. 5
shall not, except as expressly provided herein, operate as a waiver of any
right, power or remedy of the Lenders or the Administrative Agent under any of
the Loan Documents, nor constitute a waiver of any provision of any of the Loan
Documents.

          (d)  This Amendment is a Loan Document.

     Section 6.  Guarantor Consent. The Guarantor hereby consents to, and agrees
to be bound by, the terms of the Credit Agreement as amended hereby and agrees
that the terms of this Amendment shall not affect in any way its obligations and
liabilities under the Loan Documents, all of which obligations and liabilities
shall remain in full force and effect and each of which is hereby reaffirmed.

     Section 7.  Execution in Counterparts. This Amendment No. 5 may be executed
in any number of counterparts and by different parties hereto in separate
counterparts, each of which, when so executed and delivered, shall be deemed to
be an original and all of which taken together shall constitute but one and the
same instrument. Delivery of an executed counterpart by telecopy shall be
effective as delivery of a manually executed counterpart of this Amendment.

     Section 8.  Governing Law. This Amendment No. 5 shall be governed by and
construed in accordance with the law of the State of New York.

     Section 9.  Headings. Section headings in this Amendment No. 5 are included
herein for convenience of reference only and shall not constitute a part of this
Amendment No. 5 for any other purpose.

                                      -4-
<PAGE>

                                             AMENDMENT NO. 5 TO CREDIT AGREEMENT
                                                      NATIONAL STEEL CORPORATION

                            [Signature Page Follows]

                                      -5-
<PAGE>

          In Witness Whereof, the parties hereto have caused this Amendment to
be executed by their respective officers and general partners thereunto duly
authorized, as of the date first above written.

                                 National Steel Corporation

                                 By:    /s/ William E. McDonough
                                      --------------------------
                                 Name: William E. McDonough
                                 Title: Treasurer

                                 Citicorp USA, Inc.,
                                    as Administrative Agent

                                 By:     /s/ David Jaffe
                                      ------------------
                                 Name: David Jaffe
                                 Title: Vice President

                                 The Fuji Bank, Limited,
                                    as Syndication Agent

                                 By:
                                      --------------------
                                 Name:
                                 Title:

                                 Citibank, N.A.,
                                    as Issuer

                                 By:
                                      ---------------------
                                 Name:
                                 Title:
<PAGE>

                                 Lenders:
                                 Bank of America, N.A.

                                 By:
                                      ---------------------
                                 Name:
                                 Title:

                                 Citicorp USA, Inc.

                                 By:     /s/ David Jaffe
                                      ------------------

                                 Name: David Jaffe
                                 Title: Vice President

                                 Comerica Bank

                                 By:  /s/ Harold A. LaCount
                                      ----------------------

                                 Name: Harold A. LaCount
                                 Title: Vice President

                                 Morgan Guaranty Trust Company of New York

                                 By:  /s/ Kimberly L. Turner
                                      -----------------------
                                 Name: Kimberly L. Turner
                                 Title: Vice President

                                 LaSalle Business Credit, Inc.

                                 By:  /s/ J. R. Costanza
                                      ------------------
                                 Name: Joseph R. Costanza
                                 Title: Senior Vice President
<PAGE>

                                 Mellon Bank, N.A.

                                 By:  /s/ John K. Walsh
                                      ------------------
                                 Name: John K. Walsh
                                 Title: Vice President

                                 National City Commercial
                                    Finance, Inc.

                                 By:  /s/ Gregory A. Godec
                                      ---------------------
                                 Name: Gregory A. Godec
                                 Title: Senior Vice President

                                 The Fuji Bank, Limited

                                 By:
                                      ---------------------
                                 Name:
                                 Title:
<PAGE>

Acknowledged and Agreed
   as of the date first above written

National Steel Pellet Company,
   as Guarantor

By:  /s/ William E. McDonough
     -------------------------
Name: William E. McDonough
Title: Treasurer<PAGE>

                                                                    Exhibit 10-C

                                Amendment No. 1
                                      to
                         Subordinated Credit Agreement

     Amendment No. 1 (this "Amendment"), dated as of May 14, 2001, by and among
National Steel Corporation (the "Borrower"), National Steel Pellet Corporation
(the "Guarantor") and NUF LLC (the "Lender") to that certain Subordinated Credit
Agreement dated as of February 28, 2001 by and among the Borrower and the Lender
(such Subordinated Credit Agreement, as heretofore amended, the "Subordinated
Credit Agreement").

                             W i t n e s s e t h:

     Whereas, the Borrower and the Lender are parties to the Subordinated Credit
Agreement; and

     Whereas, pursuant to the Section 10.1 of the Subordinated Credit Agreement
and in anticipation of Amendment No. 5 to the Senior Credit Agreement the
parties hereto wish to amend the terms of the Subordinated Credit Agreement as
set forth herein;

     Now, Therefore, in consideration of the foregoing, the mutual covenants and
obligations herein set forth and other good and valuable consideration, the
adequacy and receipt of which is hereby acknowledged, and in reliance upon the
representations, warranties and covenants herein contained, the parties hereto,
intending to be legally bound, hereby agree as follows:

          Section 1.  Defined Terms.  Capitalized terms used herein but not
defined herein shall have the definition given to them in the Subordinated
Credit Agreement.

          Section 2.  Amendments.

          The Subordinated Credit Agreement is, effective as of the Amendment
Effective Date, amended as follows:

          (a)  Amendments to Article I (Definitions, Interpretation and
Accounting Terms)

               (1)  A definition of "Amendment Effective Date" is hereby
     inserted in Section 1.1 (Defined Terms) of the Subordinated Credit
     Agreement immediately prior to the definition of "Applicable Margin" to
     read in its entirety as follows:

          "Amendment Effective Date" means the date on which all conditions of
     effectiveness set forth in Section 3 of Amendment No. 1 to this Agreement,
     dated as of May 14, 2001, among the Borrower, the Guarantor and the Lender
     shall be satisfied.

<PAGE>

                                                              Amendment No. 1 to
                                                   Subordinated Credit Agreement
                                                      National Steel Corporation

               (2)  A definition of "Granite City Assets" is hereby inserted in
     Section 1.1 (Defined Terms) of the Subordinated Credit Agreement
     immediately prior to the definition of "Guarantor" to read in its entirety
     as follows:

          "Granite City Assets" means the "Equipment," "Inventory," "Trademarks"
     and "Other Assets," each as defined in Schedule 7.7 (Granite City Assets),
     having an aggregate Fair Market Value for all such assets not in excess of
     $3,000,000.

               (b)  Amendment to Article VII (Negative Covenants).

               (1)  Clause (a) of Section 7.7 (Sale of Assets) of the
     Subordinated Credit Agreement is hereby amended and restated in its
     entirety to read as follows:

          "(a)  The Borrower will not, and will not permit any of its Material
     Subsidiaries to, engage in any Asset Sale, except, (i) the sale of Accounts
     and certain related property pursuant to the Receivables Purchase Facility
     to the extent permitted under the Intercreditor Agreement, (ii) any Asset
     Sale permitted under Section 4.08 (Limitation on Sale of Mortgaged
     Property) or (other than an Asset Sale involving any Collateral) Section
     4.10 (Limitation on Sale of Assets Other than Mortgaged Property) of the
     Indenture, and (iii) as long as no Default or Event of Default is
     continuing or would result therefrom, the sale of the Granite City Assets
     for Fair Market Value, payable in cash upon such sale; provided, however,
     that with respect to such sale of Granite City Assets, (x) the aggregate
     consideration received for such sale shall not exceed $3,000,000 and (y)
     all Net Cash Proceeds of such sale, other than Net Cash Proceeds from the
     sale of "Equipment" set forth on and as defined in Schedule 7.7 (Granite
     City Assets), are applied to the prepayment of the Senior Loan Obligations
     to the extent required by Section 2.9 (Mandatory Prepayments) of the Senior
     Credit Agreement."

               (c)  Amendment to Schedules.

               (1)  A new Schedule 7.7 (Granite City Assets) is hereby added to
     the Subordinated Credit Agreement to read in its entirety as set forth in
     Exhibit A hereto.

          Section 3.  Conditions of Effectiveness.  This Amendment No. 1 shall
become effective when, and only when, each of the following conditions shall
have been satisfied or duly waived by the Lender (the "Amendment Effective
Date"):

               (a)  Amendment No. 5 to the Senior Credit Agreement. All
     conditions precedent to the effectiveness of Amendment No. 5 to the Senior
     Credit Agreement, other than the execution and delivery of this Amendment,
     shall have been satisfied or duly waived by the Administrative Agent.

                                      -2-
<PAGE>

                                                              Amendment No. 1 to
                                                   Subordinated Credit Agreement
                                                      National Steel Corporation

          (b)  Representations and Warranties.  Each of the representations and
     warranties contained in Article IV (Representations and Warranties) of the
     Subordinated Credit Agreement, the other Loan Documents or in any
     certificate, document or financial or other statement furnished at any time
     under or in connection therewith are true and correct in all material
     respects on and as of the Amendment Effective Date as if made on and as of
     such date, except to the extent that such representations and warranties
     specifically relate to a specific date, in which case such representations
     and warranties shall be true and correct in all material respects as of
     such specific date; provided, however, that references therein to the
     "Subordinated Credit Agreement" shall be deemed to include this Amendment;

          (c)  Corporate and Other Proceedings.  All corporate and other
     proceedings, and all documents, instruments and other legal matters in
     connection with the transactions contemplated by this Amendment shall be
     satisfactory in all respects in form and substance to the Lender.

          (d)  No Event of Default.  No Event of Default or Default shall have
     occurred and be continuing on the Amendment Effective Date.

          (e)  Fees and Expenses Paid.  On the Amendment Effective Date the
     Borrower shall have paid all reasonable costs and expenses of the Lender in
     connection with the preparation, reproduction, execution and delivery of
     this Amendment and all other Loan Documents entered into in connection
     herewith, including the reasonable fees and out-of-pocket expenses of
     counsel for the Lender with respect thereto and all other Loan Documents
     and payment of all costs, expenses and fees due under any Loan Document.

     Section 4.  Representations and Warranties.  On and as of the Amendment
Effective Date, after giving effect to this Amendment No. 1, the Borrower hereby
represents and warrants to the Lender as follows:

          (a)  This Amendment has been duly authorized, executed and delivered
     by the Borrower and constitutes a legal, valid and binding obligation of
     the Borrower, enforceable against the Borrower in accordance with its
     terms;

          (b)  Neither this Amendment nor the consummation of the transactions
     contemplated hereunder constitute a breach of the Indenture or the
     Receivables Purchase Facility;

          (c)  Each of the representations and warranties set forth in Article
     IV (Representations and Warranties) of the Subordinated Credit Agreement,
     the other Loan Documents or in any certificate, document or financial or
     other statement furnished at any time under or in connection therewith are
     true and correct in all material respects on and as of the Amendment
     Effective Date, except to the extent that such representations and
     warranties specifically relate to a specific date, in which case the
     representations and warranties shall be true and correct in all material
     respects as of such specific date; provided, however, that references
     therein to the " Subordinated Credit Agreement" shall be deemed to include
     this Amendment; and

                                      -3-
<PAGE>

                                                              Amendment No. 1 To
                                                   Subordinated Credit Agreement
                                                      National Steel Corporation

          (d)  No Default or Event of Default has occurred and is continuing.

     Section 5.  Reference to the Effect on the Loan Documents.

          (a)  As of the Amendment Effective Date, on and after the date hereof,
each reference in the Subordinated Credit Agreement to "this Agreement,"
"hereunder," "hereof," "herein," or words of like import, and each reference in
the other Loan Documents to the Subordinated Credit Agreement, shall mean and be
a reference to the Subordinated Credit Agreement as amended hereby, and this
Amendment and the Subordinated Credit Agreement shall be read together and
construed as a single instrument. The table of contents, signature pages and
list of Exhibits and Schedules of the Subordinated Credit Agreement shall be
modified to reflect the changes made in this Amendment.

          (b)  Except as specifically amended herein, the Subordinated Credit
Agreement and all other Loan Documents shall remain in full force and effect and
are hereby ratified and confirmed.

          (c)  The execution, delivery and effectiveness of this Amendment No. 1
shall not, except as expressly provided herein, operate as a waiver of any
right, power or remedy of the Lender under any of the Loan Documents, nor
constitute a waiver of any provision of any of the Loan Documents.

          (d)  This Amendment is a Loan Document.

     Section 6.  Guarantor Consent.  The Guarantor hereby consents to, and
agrees to be bound by, the terms of the Subordinated Credit Agreement as amended
hereby and agrees that the terms of this Amendment shall not affect in any way
its obligations and liabilities under the Loan Documents, all of which
obligations and liabilities shall remain in full force and effect and each of
which is hereby reaffirmed.

     Section 7.  Execution in Counterparts.  This Amendment No. 1 may be
executed in any number of counterparts and by different parties hereto in
separate counterparts, each of which, when so executed and delivered, shall be
deemed to be an original and all of which taken together shall constitute but
one and the same instrument. Delivery of an executed counterpart by telecopy
shall be effective as delivery of a manually executed counterpart of this
Amendment.

     Section 8.  Governing Law.  This Amendment No. 1 shall be governed by and
construed in accordance with the law of the State of New York.

     Section 9.  Headings.  Section headings in this Amendment No. 1 are
included herein for convenience of reference only and shall not constitute a
part of this Amendment No. 1 for any other purpose.

                            [Signature Page Follows]

                                      -4-
<PAGE>

                                                              Amendment No. 1 To
                                                   Subordinated Credit Agreement
                                                      National Steel Corporation

          In Witness Whereof, the parties hereto have caused this Amendment to
be executed by their respective officers and general partners thereunto duly
authorized, as of the date first above written.

                                 Borrower:

                                 National Steel Corporation

                                 By: /s/  William E. McDonough
                                     --------------------------
                                 Name: William E. McDonough
                                 Title:  Treasurer
<PAGE>

                                                              Amendment No. 1 To
                                                   Subordinated Credit Agreement
                                                      National Steel Corporation

                                 Lender:

                                 NUF LLC

                                 By: /s/  Mineo Shimura
                                     -------------------
                                 Name: Mineo Shimura
                                 Title: President
<PAGE>

                                                              Amendment No. 1 To
                                                   Subordinated Credit Agreement
                                                      National Steel Corporation

                              Guarantor:

                              Acknowledged and Agreed
                              as of the date first above written

                              National Steel Pellet Company

                              By: /s/ William E. McDonough
                                  -------------------------
                              Name: William E. McDonough
                              Title: Treasurer

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00028-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00028-of-00352.parquet"}]]