Exhibit 4(b)

                                 AMENDMENT NO. 1
                     TO AMENDED AND RESTATED TRUST AGREEMENT
                            DATED AS OF MARCH 1, 1996


                  Reference is made to an Amended and Restated Trust  Agreement,
dated as of March 1, 1996, among Minnesota Power & Light Company,  as Depositor,
The Bank of New York, as Property Trustee,  The Bank of New York (Delaware),  as
Delaware Trustee and Philip R. Halverson, David G. Gartzke and James K. Vizanko,
each  in his  individual  capacity  as an  Administrative  Trustee  (the  "Trust
Agreement").  Capitalized  terms not otherwise defined herein shall be used with
the meanings ascribed to them in the Trust Agreement.

                  Pursuant to the provisions of Section  10.03(a)  thereof,  the
Trust  Agreement is hereby  amended,  effective  upon delivery of notice of this
Amendment No. 1 to the Securityholders,  by the addition of the following to the
end of the last sentence of Section 4.01(d):

         ; provided that, at any time the sole  Securityholder  of the Preferred
         Securities is the Securities  Depository,  the record date shall be one
         Business Day prior to the relevant Distribution Date.

                  In witness whereof, the undersigned have executed this 
Amendment No. 1 this 11th day of April, 1996.


                                MINNESOTA POWER & LIGHT COMPANY,
                                   as Depositor

                                By:  R. D. Edwards
                                   -----------------------------------------
                                     Robert D. Edwards, Executive Vice
                                       President


                                Philip R. Halverson
                                --------------------------------------------
                                Philip R. Halverson, solely in his
                                capacity as Administrative Trustee


                                D. G. Gartzke
                                --------------------------------------------
                                David G. Gartzke, solely in his
                                capacity as Administrative Trustee


                                James Vizanko
                                --------------------------------------------
                                James K. Vizanko, solely in his
                                capacity as Administrative Trustee