AIG's Ex-Boss to Stay Mum in Probe NEW YORK (Reuters) - The former head of insurance powerhouse American International Group Inc., Maurice "Hank" Greenberg, will not answer questions on Tuesday from regulators looking into improper transactions by AIG, his lawyer David Boies said in a statement. Greenberg needed more time to prepare for the questioning by the U.S. Securities and Exchange Commission and New York State Attorney General Eliot Spitzer, Boies said on Monday, citing a "great number" of transactions under investigation, the "thousands of documents" and the fact that some deals took place five to 20 years ago. Boies added in the statement that requests to postpone the Tuesday subpoena date were denied. Separately, billionaire investor Warren Buffett told the regulators in a meeting on Monday that he did not know details of a suspect transaction between the General Re Corp. unit of his Berkshire Hathaway Inc. (BRKa.N: Quote , Profile , Research ) and AIG (AIG.N: Quote , Profile , Research ) that allegedly boosted AIG's reserves and was accounted for incorrectly, said the source, who asked not to be named. In response to reporters' questions as he made his way to a waiting car after the meeting, Buffett said, "I told them everything I know." Buffett was being questioned as a witness. Greenberg is a key figure in the investigations being conducted by Spitzer, the SEC and the Justice Department. Investigators want to pinpoint Greenberg's involvement in questionable transactions, though the case remains "wide open" and criminal charges might never be filed, a person familiar with the matter said last week. Greenberg's attorneys unanimously advised him to "respectfully decline to testify until all relevant documents have been provided to him and he is fully prepared," the statement said. Greenberg himself is quoted in the release as saying: "I was familiar with many, but certainly not all, or even a significant percentage of, the literally millions of transactions each year in approximately 130 countries," and that many decisions and actions were taken by others "without my participation." In the United States, protection against self-incrimination can be invoked under the Fifth Amendment to the Constitution. (Additional reporting by Paul Thomasch and Arindam Nag) Quelle "AIG's Ex-Boss to Stay Mum in Probe" : reuters.com Main page for "AIG's Ex-Boss to Stay Mum in Probe"