Russian Special Envoy for Kosovo Viktor Chernomyrdin's opinion piece in the Washington Post exposes the depth of the division between Russia and Nato on Kosovo, and undermines the Clinton administration's campaign to suggest that Moscow is a willing proxy negotiator, working on behalf of the Nato powers.

The Russian envoy appears particularly irritated by President Clinton's assertion in the 16 May edition of the New York Times that "Russia is now helping to work out a way for Belgrade to meet [Nato] conditions".

In fact, Mr Chernomyrdin said "these Nato goals run counter to Russia's stance," which calls for UN (not Nato) forces to be brought into Kosovo and for the Yugoslav province to remain just that, rather than some kind of international protectorate.

Blow to Nato

The Russian envoy warns that unless the air campaign is halted soon, he will advise President Yeltsin to "suspend Russian participation in the negotiating process, put an end to all military-technological co-operation with the United States and Western Europe, put off the ratification of Start II and use Russia's veto as the United Nations debates a resolution on Yugoslavia."

Such words are not taken lightly here. Mr Chernomyrdin is well respected in the United States as a cool head and an experienced diplomat.

With the American Vice-President Al Gore, he set up an enduring forum for dialogue between the two countries, and Washington has favoured a Russian interlocutor with Belgrade to re-enforce the message to President Milosevic that even his old friends in Moscow are against him.

If Mr Chernomyrdin walked away from the table it would be a political boost for Belgrade, and a severe blow to Nato.

Blow to US-Russian relations

After Kosovo, a US/Russia rift could remain

The other threats are of less concern, in the short term at least.

Start II ratification has been stalled for years, and the UN Security Council appears unlikely to put forward a resolution on Yugoslavia until the war is effectively over, because China has already made clear that it would use its own veto, unless Nato stops the bombing first.

But promoting Russian stability, and disarmament remain long term American priorities and its clear that two months of Nato's campaign have more or less destroyed the kind of political atmosphere in Russia that might be receptive any new American initiatives - especially a Start III arms reduction agreement.

The United States has clearly made the decision that it will not hold its Kosovo policy hostage to Russian sensitivities, and that Moscow needs international financial assistance too badly to be able to carry a grudge for long.

But Mr Chernomyrdin says the Nato campaign has set back the US-Russian relationship "by several decades", and sent Russian public opinion of the United States into a nosedive.

Politicians in Russia, like those in any democracy are vulnerable to such mood swings, and the Nato campaign may well boost nationalist and anti-American elements in Russian politics.

When the dust finally clears from Nato's campaign over Yugoslavia, Washington may find itself having to deal with lasting collateral damage to its relationship with Moscow as well.