The Federal Yugoslav Parliament voted to join the alliance by a massive majority - the result vote was also taken on behalf of Montenegro, the smaller part of the Serb-dominated Yugoslav federation.

But Montenegrin officials have rejected the vote and said they would rather see their future in the European Union and Nato's Partnership for Peace program for non-member countries.

Branko Perovic: This was an illegitimate vote

The Montenegrin foreign minister, Branko Perovic has said the vote was not legitimate and showed blatant disregard for Yugoslavia's federal constitution.

"Montenegro has been represented by some other representatives which were not elected by the Montenegrin parliament," Mr Perovic said.

Strained alliance

Mr Perovic said strains between Montenegro and Serbia were reaching breaking point, with the Yugoslav President Slobbodan Milosevic showing blatant disregard for Yugoslavia's federal constitution.

"With every day that passes there is less and less likelihood that we can remain in this federation," Mr Perovic said.

He said he believed the issue of independence would get a favourable response from Montenegrins if it was put to a democratic referendum.

"I do believe that the answer will be yes we would like to see a better life just because what we have had part in all these ten years by the Milosevic leadership in Serbia and Yugoslavia is quite disastrous and it is a huge waste of time," he said.

Refugees have been flooding into Montenegro

Since the pro-Western government of President Milo Djukanovic took power in Montenegro last year, the republic has been distancing itself from the Belgrade regime.

But although the government refuses to recognise the authority of the federation and its institutions, it faces strong opposition supporters of President Milosevic.

Recent polls showed less than 50% of Montenegrins wanted to severe ties with Serbia and form their own state.

Government officials say secret opinion polls taken since the Nato operation began showed support for the fervently pro-Milosevic opposition had jumped.

Mr Perovic also described the vote on the Slavic alliance as a "gross manipulation" of the Yugoslav people.

Milo Djukanovic: distancing himself from Belgrade

"It is aimed at diverting the attention of the citizens of Yugoslavia from the real cause of the current catastrophic situation which is the result of his (Milosevic's) destructive policy.

Mr Perovic said he hoped Serbia would soon "wake up to what Milosevic has done", and push him from power as a result of his "failed strategy" over Kosovo.

"It is clear that if Milosevic stays in office there is no hope for any of us to be a success and join the international community," he said.