(Bloomberg) ? John Houldsworth, a former executive at Berkshire Hathaway Inc.?s General Re unit who agreed to cooperate with US prosecutors earlier this week, pleaded guilty to a criminal charge of helping American International Group Inc. manipulate its finances.

Houldsworth, 46, was charged with one count of conspiring to file false financial reports, which carries a prison term of as much as five years. He entered his plea yesterday in federal court in Alexandria, Virginia, fulfilling an agreement with the Department of Justice announced on June 6.

?He?s accepting responsibility for his actions,? Houldsworth?s lawyer, Larry Byrne, said after the hearing. He was released on a $75,000 bond.

The Dublin-based executive admitted to helping structure a reinsurance transaction in 2000 that permitted AIG to overstate its reserves for claims. His cooperation may increase pressure on other people involved in the deal, which led to the ouster of AIG?s chairman and chief executive, Maurice (Hank) Greenberg, in March.

Judge Claude Hilton of the Eastern District of Virginia yesterday delayed a sentencing hearing to December 9 to allow more time for Houldsworth to cooperate with prosecutors. Houldsworth also plans to settle a civil suit filed June 6 by the US Securities and Exchange Commission.

The SEC said in its complaint that former General Re chief financial officer Elizabeth Monrad, senior vice president Richard Napier and former chief executive officer Ronald Ferguson also knew that AIG, the world?s largest insurer, intended to misuse the policy.

In addition to helping to structure the deal, Houldsworth created false documents to disguise its true nature, the SEC said in its complaint.

The transaction sparked an accounting investigation that uncovered an array of other improper transactions. Last month AIG restated five years of financial reports, lowering net income by $3.9 billion, or ten percent.

Houldsworth was chief executive of General Re?s Cologne Re unit in Dublin at the time of the AIG transaction. He was put on leave last month and fired after announcing the plea agreement this week. He has travelled to the US four times so far to meet with federal investigators and plans to cooperate more, Byrne said. In addition to possible prison time, the charge carries a fine of as much as $250,000.

Attorneys for Monrad, Napier, and Ferguson didn?t return phone calls. Monrad?s lawyer, Paul Shechtman, earlier this week said that ?when all the facts are known, it will be clear that Ms Monrad acted properly.?

Warren Buffett, the billionaire chairman of Berkshire Hathaway, said at the company?s April 30 annual shareholders meeting that General Re will be judged by whether it had ?knowing participation? in the misdeeds of clients. AIG is one of the three General Re clients under scrutiny by investigators.