By Belgrade correspondent Jacky Rowland

Opposition parties in Serbia are preparing to celebrate the Orthodox New Year in a greater state of unity than at any stage in the past year.

Rival opposition leaders are encouraging their followers to attend New Year's festivities organised by the student movement, Otpor (Resistance), on Thursday in Republic Square, the traditional venue for anti-government demonstrations.

The new year message comes after 15 opposition parties signed an agreement on Monday outlining political reforms aimed at removing President Slobodan Milosevic from power.

All major opposition parties are demanding presidential, parliamentary and local elections in Serbia before the end of April.

They are threatening to press their demands using a new wave of street protests starting in March.

The new action plan was drawn up by Vuk Draskovic, the mercurial politician who is now trying to assume the role of heir apparent to the opposition leadership.

Looking to the future

The document outlines a strategy for rehabilitating Serbia in the international community.

It contains proposals for the lifting of sanctions against Belgrade once the authorities agree to elections and for the re-admission of Serbia into European and international organisations.

The decision by all major parties to support the strategy indicates a new pragmatism on the part of the opposition, whose disunity in the past has alienated the people of Serbia.

Mr Draskovic's strategy is based on elections and does not include a call for the immediate removal of President Milosevic.

At the same time he is cultivating potential dissidents within Mr Milosevic's ruling Socialist Party with the aim of widening his base of support.

According to the election timetable in Serbia, local elections must be held this year. But parliamentary and presidential elections do not fall due until 2001.

However, Socialist party spokesman Ivica Dacie said: "There is no parliamentary crisis in Serbia to give a reason for calling early elections."

Smear campaign

Political analysts in Belgrade predict that the government will call local elections for April or May, capitalising on recent changes to the voting system which should favour the Socialist party and its allies.

In a sign that the authorities are worried by the new display of opposition unity, government officials have started a campaign to discredit Mr Draskovic.

The federal information minister, Goran Matic, showed journalists a videotape in which an alleged spy claimed to have put Mr Draskovic in contact with the French secret services.

Mr Draskovic, who already claims to have been the victim of a state-sponsored assassination plot, has rejected these allegations.