Maurice “Hank” Greenberg, the former chief executive of American International Group, has lambasted the insurance giant for denying him the opportunity to bid for any businesses that it may put up for sale to repay a loan of $85 billion (£47 billion) from the US Government.

Mr Greenberg, who left AIG amid an accounting scandal in 2005 but remains its largest shareholder with a 10 per cent stake, has sent the insurer a letter in which he formally requested the chance to submit an offer for any assets that come up for sale. He accused the group of failing in its fiduciary duty to achieve the “best possible price” for investors, by blocking him from any auction.

AIG has not said which businesses it plans to sell, but is expected to publish a list tomorrow when it updates investors on the company’s plans. It could also announce one or more deal agreements.

International Lease Finance, AIG’s aircraft leasing unit, American General, its US life insurance and annuity arm, and its 59 per cent stake in the Transatlantic reinsurance business are among operations that the insurer is considering putting up for sale.

In a letter to Edward Liddy, who took over the running of AIG two weeks ago after its government bail-out, Mr Greenberg criticised the group for barring him from getting involved in any rescue of the company. “For a considerable period of time . . . AIG has declined my assistance and refused to meet with me even to provide me with the information that would be necessary to try to assist the company on my own,” Mr Greenberg said in his letter, dated September 29.

He continued: “I now understand that the company has begun to liquidate itself by selling assets in privately negotiated transactions without transparency and without providing the opportunity for the participation of alternative purchasers that would be required to obtain the best possible price for shareholders.

“I want to formally request an opportunity to submit an offer on any assets that the company intends to sell. It is, of course, clear that you have a fiduciary duty to obtain the best possible price for the benefit of shareholders and creditors in any sale of assets and that you cannot do so by ignoring offers from qualified potential purchasers.”

AIG is seeking to raise cash to bolster its financial strength as quickly as possible. Some investors had hoped that a quick asset sale might prevent the Government taking up preferred shares representing 79.9 per cent of the voting rights of the group, as one of the conditions of the loan to it. However, in a regulatory filing on September 26, AIG said that the Government would take up its shares “even if the credit facility is repaid in full”.

A spokesman for AIG confirmed that the group had received Mr Greenberg’s letter. He added: “We are open to all reasonable expressions of interest in the assets we plan to sell.” The spokesman declined to confirm whether AIG viewed any potential offer from Mr Greenberg as a reasonable expression of interest.

Mr Greenberg, 83, joined AIG as a vice-president in 1960, when it was a small insurance group. He became president eight years later and set about transforming it into a global insurance giant with $800 billion of assets. In 2005, he was forced to resign amid allegations by Eliot Spitzer, the New York state attorney-general at the time, that he had inflated the company’s results through a series of fraudulent transactions.

AIG later reduced its results by $3.9 billion in connection with these transactions and others. Mr Greenberg was not a defendant in a criminal case arising from these transactions, although prosecutors called him an unindicted co-conspirator. A three-year-old civil case against Mr Greenberg continues after he and the New York attorney-general’s office failed to reach a settlement.

— Sigma Finance, a $27 billion structured investment vehicle run by Gordian Knot, has ceased trading. It was the oldest and last surviving independent of the complex debt funds that have been embroiled in the credit crisis. Bondholders may face significant losses.

Insurance schedule

Tuesday September 23: AIG announces it has agreed an $85 billion loan from the US Government in return for shares representing 79.9 per cent of the voting rights

Thursday September 25: It emerges that the FBI is investigating AIG, among others, to see if it pressured ratings agencies into inflating the ratings on the bonds they issued and whether senior executives misled the market about the true value of its assets

Monday September 29: Maurice “Hank” Greenberg writes letter to AIG lambasting it for ignoring his requests to help the company and to participate in the sale of any assets

Tuesday September 30: AIG sells its 50 per cent stake in London City Airport to Global Infrastructure Partners, owner of the other half

Friday October 3: AIG set to update the market on its plan to dispose of key assets

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