In an interview earlier this week, Mr Salmond said Nato's campaign was an "unpardonable folly".

Mr Cook said he would be the "toast of Belgrade" for his anti-bombing stance.

Salmond says Nato's bombing will strengthen Milosevic's position

Now Mr Salmond has hit back with a letter complaining of a "New Labour smear machine".

He accused Mr Cook of misrepresenting what he had said.

"Given your opposition to the bombing of Baghdad in 1991, do you not find that your actions now towards me are tinged with hypocrisy?" Mr Salmond wrote.

"And will you not admit that the actions of you and those around you are now focused on this matter for Scottish electoral purposes, to the great detriment of the issue itself and its proper consideration?"

Speaking earlier on BBC Radio 4's Any Questions, Mr Salmond said that he supported the servicemen, but they had been sent to carry out an "impossible job".

Mr Salmond said he found Mr Milosevic "repellent"

Mr Salmond said: "The plight of the Kosovar Albanians is incomparably worse than it was this time last week when the bombing campaign started, and it's consolidated the position of the tyrant Milosevic within Serbia.

"Up until this point, the Nato strategy has been entirely counterproductive in what I have no doubt are the laudable aims that it has.

"I maintain my right to criticise a strategy I think is entirely counterproductive and wrong-headed.

"It is making things must worse for people on the ground who you cannot protect from 20,000ft."

'Spell out objectives'

Conservative Party Chairman Michael Ancram called on Nato to spell out more clearly what their aims were in the air strikes on Yugoslavia.

Following the bombardment of police and military buildings in central Belgrade, he told BBC Radio 4's Today programme: "What we have seen overnight is a serious ratcheting-up of the Nato action.

"We have made clear we generally support what Nato's doing.

"But we need to know what the objectives are, what this bombing is going to achieve, if it's intended to bring Milosevic back to the table.