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                                                                   EXHIBIT 23(A)
 
                       CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS
 
     As independent public accountants, we hereby consent to the incorporation
by reference in this registration statement on Form S-4 of our report dated
January 29, 1996, included in UST Corp's Form 10-K for the year ended December
31, 1995 and to all references to our Firm included in this registration
statement.
 
                                            /S/ ARTHUR ANDERSEN LLP
                                            -----------------------
                                            ARTHUR ANDERSEN LLP
 
Boston, Massachusetts
October 30, 1996