(Bloomberg) ? Maurice (Hank) Greenberg, who was ousted in March as chairman and chief executive officer of insurer American International Group Inc. amid an accounting probe, resigned from his remaining post of director earlier than planned.

Greenberg, 80, was to continue to hold the post until this year?s elections, which have yet to be scheduled. He hasn?t been attending board meetings since March, said AIG spokesman Chris Winans, who declined to comment on the resignation.

?I previously stated my intention not to stand for re-election to the board,? Greenberg wrote in a letter to the board released to the Press late on Wednesday. ?My decision to resign now results from my inability to receive information regarding the company and its operations necessary to fulfil my fiduciary duties.?

Greenberg, who had been CEO for almost 40 years, was forced to step down after New York Attorney General Eliot Spitzer began investigating a type of reinsurance that insurers may abuse to smooth earnings or mask losses. Spitzer has since sued Greenberg and AIG, accusing them of using improper accounting on reinsurance contracts and other transactions to dupe investors and regulators. The investigation prompted AIG, the world?s largest insurer, to lower net income from the past five years by $3.9 billion, or ten percent.