Treasury Secretary Lawrence H. Summers defended the Clinton administration's Russia policy yesterday, saying that U.S. officials have always made ending financial corruption in Russia a top priority but that those concerns must be weighed against political reality.

"At every step, we have been clear-headed in endeavoring to strike a careful balance between . . . what is best economically and is also politically realistic," Summers said.

Summers made his remarks on the opening day of House Banking Committee hearings into allegations of money laundering and Russian corruption. Lawmakers organized the hearings after recent publicity concerning a year-long federal probe into whether as much as $5 billion passing through several accounts at the Bank of New York was linked to Russian capital flight or illegal activities.

Swiss and British prosecutors are also conducting investigations that may involve high-level Russian officials or organized crime.

Swiss banks have frozen $16.8 million in accounts suspected of being linked to the Bank of New York case, Swiss officials said yesterday. No one has been charged, and U.S. law enforcement officials said they have thus far not found proof that Russian organized crime is involved or much evidence that would lead to prosecution under U.S. money-laundering laws.

Yet several Republican and Democratic lawmakers yesterday criticized Treasury officials for what they characterized as a failure to adequately pressure Russia to weed out financial and political corruption in exchange for loans and other aid, and for what lawmakers described as a general laxity in cracking down on money laundering.

"Not one bank has ever lost its charter over money laundering," said Rep. Maxine Waters (D-Calif.). Money laundering is a catch phrase for complex banking activities designed to obscure the origin and ultimate destination of funds.

Summers reiterated the administration's long-held position that it won't support any new monetary aid to Russia, by either the International Monetary Fund or the World Bank, unless the aid is tied to reforms. Currently, any new IMF loans to Russia merely roll over previous loans, without the money ever passing through Russian hands.

As expected, House Banking Committee Chairman Jim Leach (R-Iowa) yesterday introduced new anti-money-laundering legislation that is widely supported by Democrats, including the committee's senior Democrat, John J. LaFalce (N.Y.). Sen. Charles E. Schumer (D-N.Y.) said he will introduce similar legislation in the Senate.

The bill would make it hard for offshore, largely unregulated banks to do business in the United States by forbidding U.S. banks to provide accounts for such institutions. The bill would also greatly expand the list of foreign crimes that U.S. officials could cite in bringing money-laundering charges. Under current law, only banking transactions designed to hide money connected to drugs, murder, kidnapping and some fraud can result in money-laundering charges. Leach's proposal would add any violent crime, any fraud against a foreign government and any misuse of foreign aid.

Offshore banks often are headquartered in Antigua, the Isle of Man or other places around the world that have liberal laws to make it easy for money to be moved secretly, without of the knowledge of tax collectors or law enforcement officials.

These banks are sometimes used to launder money. But offshore banks also can provide legitimate tax shelters, congressional and industry sources say. That's likely to mean Leach's proposal will face a major lobbying fight by banks and corporations, sources said.