It’s official: Maurice “Hank” Greenberg has stepped down as chief executive officer of American International Group as part of a major shakeup at the insurance giant. He will remain as chairman, however.

Co-chief operating officer and vice chairman Martin Sullivan, who joined the company in 1971, will take on the roles of CEO and president.

Almost totally overlooked, however, was AIG’s simultaneous announcement that chief financial officer Howard Smith “has taken leave.” Assuming his responsibilities will be Steven Bensinger, who has been named executive vice president and CFO.

And Donald Kanak, who was vice chairman and co-chief operating officer with Sullivan, 52, was named executive vice chairman and COO, focusing on Asia.

“The board has concluded it is now in the best interest of AIG’s shareholders, customers, and employees to turn to a new generation of leadership,” said Frank Zarb, chairman of the executive committee of AIG’s board of directors, in a statement, according to Bloomberg.

Bensinger, who joined the company in 2002, will also retain his current titles of treasurer and comptroller. Prior to joining AIG, Bensinger was executive vice president and CFO of Combined Specialty Group Inc., the insurance underwriting operations of Aon Corp. Before joining Aon, he was executive vice president of Trenwick Group Ltd., a position he assumed in October 1999 when Trenwick acquired Chartwell Re Corp., where Bensinger served as president and a director.

AIG also announced that it will delay the filing of its 2004 annual report, which is due on Wednesday. In a statement, the company stressed that the delay is the result of the management changes as it continues its internal review of accounting for certain transactions. “The company does not believe that any of the matters subject to the review are likely to result in significant changes to the company’s financial position,” added AIG.

Greenberg’s ouster follows the recent departures of chief executives at Hewlett-Packard Co. and Boeing Co. All the more reason, as CFO examined in its January cover story “Across the Board,” that directors and CFOs must forge a new relationship.