In a sharp break with tradition, the European allies are taking a more assertive approach than the United States in demanding that Russia halt its scorched-earth offensive against Chechnya or face possible economic sanctions for brutalizing the civilian population.

The leaders of Germany, France, Italy and Britain have bluntly informed Moscow that its military crackdown against Chechnya's separatist rebellion is failing and will soon provoke an international backlash that could further imperil Russia's weak economy.

During past Russian crises, Europe has often balked when the threat of Western sanctions was invoked. In considering how to respond to Moscow's 1979 invasion of Afghanistan, its suppression of dissidents during the Cold War or the first Chechen war in 1994-96, European governments invariably opted for a low profile to preserve business as usual.

But the hard-nosed approach adopted in the face of Russia's "flee or die" ultimatum to residents of the Chechen capital of Grozny appears to signal a dramatic change in dealing with a vast but enfeebled eastern neighbor that is still regarded as one of the most volatile threats to the continent's security.

Diplomats on both sides of the Atlantic say the change in Europe's attitude toward Russia has been nurtured in part by lingering embarrassment about U.S. dominance of the NATO air campaign against Yugoslavia during the Kosovo crisis. It also reflects a new determination by the Europeans to seize the initiative in dealing with future crises that are much closer to home for them than for the United States.

"We learned a serious lesson in Kosovo," explained a senior European diplomat at NATO headquarters in Brussels. "Unless we act in a decisive and united way, the Americans will take control of the situation and force us to adopt their approach."

In contrast to Europe's call for action, Washington has adopted a more cautious tack. In private talks with other allied leaders, European officials say, President Clinton has warned that Western countries must avoid hurting their own interests by taking measures that further destabilize the Russian economy and contribute to the resurgence of anti-Western nationalists.

When asked at a news conference in Washington today why the United States pushed for sanctions to punish repression by Yugoslavia and Indonesia but not by Russia, Clinton said such a gesture would be superfluous because as a permanent member of the United Nations Security Council, Russia would be able to veto any proposed sanctions.

Clinton also noted that two-thirds of American aid to Russia is devoted to nuclear safeguards, with the remainder funding projects that encourage the growth of democracy. He expressed reluctance to see those investments jeopardized by punitive actions, saying, "Russia is already paying a heavy price" for its war in Chechnya.

Despite frequent analogies drawn between Serbia's crackdown against separatist ethnic Albanians in Kosovo and the Russian attack against Chechen separatists, Western governments have been careful to distinguish between the two conflicts and emphasize that there is no question of undertaking military action to force Russia to back down.

But leaders of the 15 European Union governments today escalated pressure on Russia to find a peaceful settlement, warning they may decide at a summit meeting in Helsinki this weekend to impose economic sanctions against Moscow unless it rescinds a threat to annihilate Chechnya's capital if residents do not leave by Saturday.

As Russia's largest creditor, Germany clearly feels that it can exercise the greatest leverage against Moscow. Chancellor Gerhard Schroeder's government is also worried that with as many as 200,000 Chechen refugees spilling out of the region, ethnic turmoil could quickly engulf the entire Caucasus.

Senior German officials said Schroeder sent an urgent message to Russian President Boris Yeltsin and Prime Minister Vladimir Putin demanding that Moscow revoke its ultimatum to Grozny's inhabitants.

The officials described the Russian deadline as "clearly illegal" and said if Moscow proceeds with plans to launch an all-out attack, it would compel the European leaders to cut off further economic aid. "It is hard to see how any more cash can flow to Russia in the current situation," a senior government official said.

The governments of France, Britain and Italy brandished similar warnings about economic punishment, reinforcing a message sent by the refusal of the International Monetary Fund to release a $640 million loan--ostensibly because Moscow has not fulfilled promises about structural economic reforms.

French President Jacques Chirac bluntly declared that Russia's behavior was "unacceptable." His spokeswoman, Catherine Colonna, said today that EU leaders would have no choice but to consider punitive action if Russia persists in its offensive.

"One cannot take an entire civilian population hostage and threaten to consider an entire civilian population as terrorists and at the same time ask us to be understanding," Colonna said.

Italian Prime Minister Massimo D'Alema contended Europe may have to proceed with economic measures against Moscow in order for its message to be heeded. "Eventual sanctions will have to be decided by the United Nations," D'Alema said. "But it is obvious that Europe has many possibilities to exercise strong pressure on Russia. We intend to use all the means at our disposal, including economic pressure."

British Foreign Secretary Robin Cook said it appeared European threats may already be having an effect. He cited a report that Russia's chief commander in Chechnya, Gen. Viktor Kazantsev, who said the ultimatum was not aimed at civilians but at making Islamic militants lay down their arms.

"I welcome the fact that we really have obviously been understood and heard in Moscow," Cook said. "But we need now to try and take this further. Should they carry out the threat, and it looks as if they will not, then we will be asking the European Union to consider the future of our help to Russia."

Cook said he believed the IMF's decision to withdraw the $640 million loan--which is part of a $4.5 billion package--had a compelling effect on Russian thinking even though it was done for economic reasons. "The IMF charter makes plain that its decision must be grounded in the economic conditions," Cook said. "But believe me, it will not be lost on Moscow that the decision was taken yesterday. They will understand the circumstances that influenced that decision."