THE scandal-torn insurance giant American International Group is this week expected to announce the results of an investigation into accounting errors that could total as much as $3 billion (€2.31 billion).

AIG, the world’s largest insurance group, is under investigation by the US authorities over deals that artificially inflated its financial strength.

Earlier this month one such deal with General Re, a unit of Berkshire Hathaway, led to the resignation of Maurice “Hank” Greenberg as AIG’s chief executive. Greenberg had led the company for nearly 40 years.

AIG and regulators are now thought to be investigating as many as 30 problematic transactions that could result in the company restating its accounts by $1.5 billion to $3 billion.

A company spokesman said he could not comment on the investigation or on the likelihood or potential size of any restatement. AIG is due to issue its annual financial report on Thursday. The results were delayed after the abrupt resignation of Greenberg.

Greenberg, who controls 16% of the $144 billion company, remains chairman but has reportedly been told he will be forced out unless he agrees to testify before the New York attorney-general Eliot Spitzer.

AIG shares have fallen 24% since announcing on February 14 that it had received subpoenas from Spitzer and the Securities and Exchange Commission (SEC) over whether it misled investors. Last week, AIG fired its chief financial officer and a senior reinsurance executive after they decided not to answer questions.

A multi-billion-dollar charge against earnings would be unlikely to affect AIG long term. It posted net income of $11.04 billion last year on revenue of $98.61 billion.