After 10 hours of talks, Yugoslavia issued a statement saying it accepted the general principles for a peace deal drawn up by Russia and the other seven G8 nations earlier this month.

Some leading politicians in Belgrade who have been lobbying the president to find a diplomatic solution were said to have been celebrating after the latest talks.

One source close to government told the BBC there had been a psychological shift on the part of the Yugoslav leader.

The BBC's Stephen Gibbs: "The basis of Chernomyrdin's optimism remains unclear"

There was now a desire for genuine cooperation with the international community, he said, and a commitment to act unliaterally, if necessary, to bring the war to an end.

Reports say the authorities have agreed to pull back forces from Kosovo even while the bombardments continue.

As Mr Chernomyrdin left Belgrade, Nato jets began another night of air strikes as the alliance signalled it would take advantage of improving weather conditions to step up its air campaign against Yugoslavia.

Reports say electrical relay stations have been targeted, leaving most of Belgrade and much of the rest of Serbia without electricity.

Belgrade's statement

In its statement, Belgrade said it accepted the G8 declaration as a basis for negotiations under the auspices of the United Nations, but remained opposed to the deployment of foreign troops in Kosovo.

Michael Williams reports from Belgrade:" Reports of a psychological shift"

As he left Belgrade, Mr Chernomyrdin indicated he would return to Yugoslavia next week with European Union representative, Finnish President Martti Ahtisaari.

The Russian news agency Itar-Tass quoted him as saying he had reached a better understanding with Mr Milosevic.

Mr Chernomyrdin said before Friday's talks that further negotiation would be pointless if Nato did not stop the air strikes.

Weather favours Nato

Novi Sad oil refinery burns

Speaking at the daily Nato briefing in Brussels on Friday, military spokesman General Walter Jertz said a total of 792 missions had been flown in the previous 24 hours - the highest number so far.

He said the intensity of the bombardment would increase still further, as the weather forecast was good for the rest of the month.

"Let me tell you what Milosevic already knows - for the next five days the weather is on our side," he said.

The ever-increasing numbers of warplanes at Nato's disposal has also enabled it to pile the pressure on Serbian forces and infrastructure.

The BBC's John Simpson: "Many of Milosevic's political enemies think the indictment was a mistake"

General Jertz said 310 of the latest missions were strike sorties and that "better numbers" would be coming up in the next few days.

Most of Belgrade and large parts of Serbia were without electricity on Friday after Nato planes bombed two electrical transformer yards and four transmission towers near the capital.

(Click here to see a map of latest Nato strikes)

At least 20 artillery pieces, as well as tanks, multiple rocket launchers and a number of anti-artillery pieces, had been hit.

The alliance also continued its attacks against airfields, military storage dumps, fuel depots and television and radio transmission installations throughout Serbia.

Air drops

An international aid organisation has announced that it is to begin dropping food to displaced people inside Kosovo within the next few days.

The International Rescue Committee announced in New York that it would fly two chartered Russian planes from Italy and drop enough food to feed 15,000 people a day.

Washinton Correspondent Paul Reynolds: "Operation co-ordinated with Nato"

Nato has resisted pressure to make food drops for the thousands of people living in the hills in Kosovo because of the risk that their planes would be shot down.

But the aid agency said it had informed the Yugoslav Government about the plan this week and that officials had had offered no negative comments.

The food will be vegetarian, to accommodate possible religous requirements by Albanian Muslims.

The cost will be a $1m a month, some of which will be paid for by the US government.

So far, the Yugoslav government has not given official permission for the air drops.

• Text of Yugoslav statement
• Aid group plans Kosovo air drops
• Nato prepares for 'Phase Three'
• KLA go on the offensive
• Analysis: Indictment raises the stakes

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