"Some people obviously aren't understanding our repeated proposals", he said, just hours after sacking his Prime Minister, Yevgeny Primakov, and the entire Russian Government.

The head of the Russian Security Council, Vladimir Putin, said Russia was unhappy playing the role of a courier, merely taking proposals from one country to another.

BBC Diplomatic Correspondent Barnaby Mason says that if the Russian remarks are meant seriously, it would destroy any chance of setting up a UN-sanctioned military force for Kosovo.

Nato Secretary-General Javier Solana said he hoped Russia would not pull out pf the negotiating process.

Mr Yeltsin's comments cast a shadow over talks in Moscow between Russia's special envoy to Yugoslavia, Viktor Chernomyrdin, and US Deputy Secretary of State, Strobe Talbott.

President Yeltsin: Wants to be heard

Mr Chernomyrdin, who has just come back from talks with the Chinese leadership in Beijing, has said he has new proposals to put to Nato.

But the Russian Foreign Minister, Igor Ivanov, said Russia was worried that Nato would ruin efforts to find a peaceful solution to the Kosovo crisis by pushing on with its air strikes.

Nato leaders have said there must be a concrete sign of their demands being met before they can end the campaign.

The alliance said on Wednesday it had carried out its busiest attacks so far the previous night.

Nato said its planes attacked bridges and airfields in Serbia, while in Kosovo, tanks and armoured vehicles were destroyed.

The BBC's Stephen Gibbs: "No signs of a deal until Nato stop bombing"

Serbian media reported strikes in suburbs of Belgrade and the death of a young girl after a Nato raid on a village in southern Serbia.

In a separate development, the United Nations High Commissioner for Refugees (UNHCR) has said it is facing a drastic shortage of money for relief efforts among Kosovo-Albanian refugees.

(Click here to see a map of last night's Nato strikes)

The first Nato leader to visit China since the embassy bombing - German Chancellor Gerhard Schröder - has apologised for the Nato attack on China's embassy.

Mr Schröder, on a one-day visit to Beijing, said: "I think the Chinese leaders have very much understood that I am very, very serious indeed when I express my emotions of compassion, sadness and my feelings of commitment to the families of the victims."

He met Chinese Premier Zhu Rongji and Foreign Minister Tang Jiaxuan, and said he had apologised for the bombing on behalf of Germany and Nato.

For its part, the Chinese Government has been showing signs of softening its criticism of the alliance campaign following the attack on its Belgrade embassy, which killed 3 people and injured 20 others.

Mark Devenport at the United Nations: "Now China has shifted its position"

China toned down its demands for a United Nations condemnation of the incident, issuing a fresh proposal urging the UN Security Council to "strongly deplore" the attack.

It also dropped calls for an official UN investigation of the bombing, and for those responsible to be punished.

In a further sign of easing tension, Beijing has been showing signs that it might be prepared to join a proposed UN peace force in the province. However, it emphasised that it would not consider any peace plan for Kosovo until the Nato bombing stopped.

However, Mr Schröder said China was resolute in its demand that Nato end air strikes on Yugoslavia before it would support a peace deal.

"I'm not trying to conceal that there are differences of assessment here," the German chancellor said.

The BBC's Jill McGivering: "A mood of national mourning in China"

His visit came as the remains of the three people killed in the embassy attack were returned to China.

A special plane carrying the victims' ashes, along with more than 20 injured and China's special investigation team, was met at Beijing Airport by a guard of honour and the Chinese vice-president, Hu Jintao.

• US used wrong map for embassy attack
• China seeks to restore calm
• 'KLA still fighting fit'
• Refugee agency's cash crisis
• Nato's bombing blunders

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