Former Russian Prime Minister Viktor Chernomyrdin demanded a formal apology on Monday from U.S. Republican presidential candidate George W. Bush for accusing him of stealing IMF money, and threatened to sue. Bush, who in last week's campaign debate attacked Vice-President Al Gore over the Democratic administration's ties with Russia, said some money lent to Russia by the International Monetary Fund had "ended up in Viktor Chernomyrdin's pockets". "Such statements are not only damaging but they are also dangerous to the public," Chernomyrdin told a news conference. "That is why I insist on a public apology. I am sure you (Bush) will present it immediately," he said. "Otherwise I will have to defend my honour in court." Chernomyrdin, who has called Bush an irresponsible politician, said the governor was well aware his remarks were also liable to affect Washington's relations with Moscow. "He knows that for the sake of his ambitions he is putting at risk future relations between the United States and Russia, two nuclear superpowers with a special responsibility for world security," he said. The IMF lent money to Russia throughout the 1990s, but most accusations that some IMF money may have been stolen have surrounded $4.8 billion in loans made in the summer of 1998, several months after Chernomyrdin was sacked as premier. The IMF has repeatedly denied that any of the money it lent to Moscow was misappropriated by the Russians, though officials are still investigating whether some of the money was siphoned off via Swiss bank accounts. The Bush campaign has stood by the Texas governor's statements, saying Chernomyrdin, a former head of natural gas monopoly Gazprom, "made a fortune in personal profits" in the Russian oil and gas business while in the cabinet. A spokesman for Bush has said the industry has benefited greatly from foreign aid, including aid from the IMF. Chernomyrdin has denied having made a fortune out of his connections with Gazprom, Reuters reports.