Macedonian Prime Minister Ljubco Georgievski has launched a fierce attack on the two international mediators attempting to broker an end to the country's bitter five-month conflict.

Mr Georgievski described the latest blueprint - aimed at a peace settlement between the country's Macedonian and Albanian communities - as "brutal interference".

He accused the two mediators, US envoy James Pardew and European Union envoy Francois Leotard, of caving in to Albanian demands, and of trying to break up the state's institutions.

Macedonia was facing an ultimatum, he said; the country was being threatened and blackmailed.

Tuesday's mood of deadlock is now turning into a full-blown crisis.

At a meeting between the mediators and representatives of all Macedonia's political parties, President Boris Trajkovski attempted to launch a debate based on an earlier set of proposals offering fewer concessions to the country's Albanian minority.

But the leading Albanian politician, Arben Xaferi, walked out, and the mediators acknowledge that getting him back to the table may not be easy.

The envoys spent Wednesday scrambling to prevent the collapse of their efforts.

Following Macedonian accusations that they were willing to grant equal status to the Albanian language, Mr Leotard and Mr Pardew were forced to issue a statement.

Their proposals retained Macedonian as the country's primary official language, they said.

Not only that, but their latest draft preserved the sovereignty and territorial integrity of Macedonia.

It had been thought that Nato Secretary-General George Robertson and EU foreign policy chief Javier Solana would arrive on Thursday to help push the process forward.

But, according to a senior Western diplomat, that visit is now off.