H.F. Ahmanson & Co. said it's asking the Securities and Exchange Commission to review the terms of Washington Mutual Inc.'s $6.14-billion agreement to acquire Chatsworth-based Great Western Financial Corp. In a letter to regulators, Irwindale-based Ahmanson said Seattle-based Washington Mutual cannot use the pooling-of-interest accounting method because it plans to repurchase shares on the open market as well as use Treasury shares for the acquisition. Washington Mutual has said its agreement depends on using the pooling method, which doesn't create "goodwill" expenses that reduce earnings following a transaction. Ahmanson cited the proposed First Bank System-First Interstate transaction, in which First Bank abandoned its bid after the SEC said it could use the pooling method only if it suspended its stock buybacks. Washington Mutual dismissed Ahmanson's move as a "desperate attempt" and its "allegation of the day." Ahmanson last week raised its hostile offer for GW to $6.18 billion.