EXHIBIT 23(A) CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS As independent public accountants, we hereby consent to the incorporation by reference in this registration statement of our report dated January 23, 1997 incorporated by reference in MDU Resources Group, Inc.'s Form 10-K for the year ended December 31, 1996, and to all references to our Firm included in this registration statement. /s/ Arthur Andersen LLP ARTHUR ANDERSEN LLP Minneapolis, Minnesota May 27, 1997