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 February 20, 1998 included in Washington Real Estate Investment Trust's Form 10-K for the year ended December 31, 1997 and to all references to our Firm in this Registration Statement. ARTHUR ANDERSEN LLP Washington, DC March 31, 1998