Speaking hours after warning Nato not to send ground troops to the region, Mr Yeltsin said: "I told Nato, the Americans, the Germans, don't push us towards military action.

"Otherwise there will be a European war for sure - and possibly world war," he said in televised comments.

However a White House spokesman said the US had been assured that Russia did not want to be pulled into the conflict

Andrew Harding in Moscow: Russia is seething with anti-western fury

Earlier, Mr Yeltsin had said that Russia could not allow the Western alliance to "seize" Yugoslavia.

But Nato spokesman Jamie Shea played down reports that Russian missiles would be retargeted at western alliance nations.

Parliamentary speaker Gennady Seleznyov had been reported as saying that the Kremlin had ordered Russian missiles to be "pointed at countries which are fighting against Yugoslavia".

Mr Shea said: "We have to take that (the threats) with a pinch of salt".

A spokesman for the Russian speaker said the remarks had been misunderstood.

Moscow has previously said it would not consider military involvement in the Balkans in any circumstances.

BBC Moscow Correspondent Andrew Harding says that with Mr Yeltsin facing a possible impeachment vote next week, his comments may be intended more to appease domestic critics than to alarm Nato.

Union mooted

Mr Seleznyov also said President Yeltsin was backing a request by the Yugoslav President, Slobodan Milosevic, for his country to join in a political union between Russia and Belarus.

Mr Seleznyov, who held talks in Belgrade this week, said Mr Yeltsin had ordered officials to draft a document on a union with Yugoslavia.

But Mr Yeltsin said on Thursday that such a union was politically and legally inopportune.

Car factory hit

In its latest wave of attacks, Nato's bombing raids were hampered by poor weather.

Click here for a map showing Nato's latest strikes

Thousands of Serbs also formed human shields to protect key bridges from Nato bombs.

There were no reports of attacks on bridges but the alliance did hit the Yugo car factory in Kragujevac, saying that it was also manufacturing arms.

Amid the bombing, Serbs celebrate Easter

Reports on state-controlled Serb television showed the factory devastated. They said120 people were injured.

Nato bombs also hit a plant providing heating to homes, hospitals, schools and kindergartens in the town, the report said.

Nato said that its initial assessment showed that there might have been "collateral damage" to civilian buildings near the factory. The alliance had no figures for casualties.

Early on Friday - Good Friday for Orthodox Christians - Serbian television showed pictures of a fuel depot exploding in the town of Smederevo east of Belgrade.

Duncan Kennedy: "The KLA is pressing Nato to supply them with arms"

Other overnight targets included a power line in Valjevo and a television transmitter, believed by Nato to be used for military communications.

On the ground in Kosovo, there have been reports of fighting between Serbian troops and Kosovo Liberation Army forces near the Albanian border.

Gunfire was exchanged in a skirmish on Friday morning, and two mortar shells landed in Albanian territory, a spokesman for the Organisation for Security and Co-operation in Europe said.

Refugee mission

In Macedonia, the United Nations High Commissioner for refugees, Sadako Ogata, has toured one of the largest tent camps for Kosovo Albanians.

She was due to meet the Macedonian president and prime minister but had already criticised the country's deporting of refugees on the border.

In Yugoslavia, the speaker of the Cyprus parliament, Spyros Kyprianou, is on a separate mission to try to secure the release of three captured American soldiers.

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The UNHCR says the number of people who have fled Kosovo since 24 March, when Nato began bombing Yugoslavia, is now more than 620,000.