Police opened fire on unidentified gunmen who tried unsuccessfully to fire a grenade launcher at the building.

The BBC's James Coomarsamy in Moscow: "Three men in stolen jeep with two grenade launchers"

The gunmen replied with two bursts of automatic rifle fire before driving off in an apparently stolen police jeep.

There are no reports of any injuries. Three suspects are reported to have been arrested.

'No change' in US position

Despite the growing protests against air strikes, US special envoy Richard Holbrooke has said there is "no change" in the American position regarding the need for the Nato action.

Attack left bullet holes

Speaking in Budapest after talks with a Russian delegation arguing a halt to the raids, Mr Holbrooke said: "There is a clear disagreement betwen the Russian Government and Nato but that does not mean we cannot still continue close contacts."

The delegation, led by the former Russian Prime Minister Yegor Gaidar, told reporters after meeting Mr Holbrooke that the Yugoslav crisis posed dangers for the world.

The BBC's Nick Thorpe in Budapest: "Russians and Americans disagree on most aspects of the crisis"

"If the situation continues in the direction it is going now, we are confronted with a serious danger of the Cold War re-emerging," Mr Gaidar said.

The delegation is hoping to go on to Belgrade to talk to President Milosevic.

Their visit is being delayed as they have still not been granted entry visas to Yugoslavia, nor guaranteed an audience with President Milosevic.

French appeal to Russia

Clinton as seen by anti-Nato protesters in Sydney

French President Jacques Chirac has appealed to Russia to do its utmost to convince Yugoslav President Slobodan Milosevic to make the moves which would end the air strikes.

Mr Chirac phoned Russian Prime Minister Yevgeny Primakov to say Russia had an important role in the search for a political settlement.

Previous Russian mediation attempts have been no more successful than those of the Americans or the Europeans. But Russia does have the advantage of a traditional friendship with Serbia.

Demonstrations against the air strikes have continued throughout Europe, in the US and in Australia.

Some Serbian protesters threw petrol bombs and rocks at the US embassy in the Danish capital Copenhagen on Saturday night.