MOSCOW. Nov 19 (Interfax) - Former acting Russian prime minister Yegor Gaidar said on Monday that he "can't see any serious risks for Russia's economy until 2010" but that "everything is much more complicated" as regards "the next 20 years" because of "very serious stability problems in the pension system."

An economic crisis that would involve defaults on major debts "is out of the question in the short and medium terms," Gaidar, who heads the Russian Institute of the Transitional Period Economy, told a news conference at Interfax headquarters in Moscow by citing an analysis by his institute of possible risks for the next three years.

"We have tried to analyze the worst possible scenarios. Of course, I can't see any serious risks until 2010," he said.

"Natural gas production does involve some specific problems, but that has nothing to do with a default. If we discuss developments not within the next three but the next 20 years, everything is much more complicated there due to very serious stability problems in the pension system, something that, strategically speaking, I consider to be one of the most serious problems of Russia, and of many other countries for that matter," Gaidar said.

Asked whether there existed potential problems for the Russian banking system, he said: "of course, they are caused by the severe problems of mortgage lending in the United States. It is a paradoxical but the logic of the international financial system that, when financial problems arise in the U.S., it is to the United States that money flows to."

"But our system has quite large reserves of stability. The Central Bank has been amazingly quick in preventing panic from gaining momentum in banking and financial markets by a series of intelligent actions," Gaidar said.

Gaidar was acting prime minister for six months in 1992.