David Trimble has survived a policy challenge that amounted to a vote of confidence in the Ulster Unionist Party leader.

At a meeting of the Ulster Unionist Council on Monday, Trimble won 54 per cent support for his participation in negotiations to restore devolution to Northern Ireland.

Hardline MP Jeffrey Donaldson had said that he would quit the party if his motion calling for the rejection of the British and Irish governments' plan for restoring power-sharing in Belfast was defeated.

After the vote Trimble called on Donaldson to remain within the UUP and fight on the party platform.

"I would like him to consider it and conclude that the only course to follow is to remain in the Ulster Unionist Party, and to support the policies of the party," he said.

"I would dearly love Jeffrey to consider that as being the only way forward in the present circumstances."

Donaldson described the result of the vote as a "pyrrhic victory" for his leader.

The 900-strong ruling council had backed Trimble in a series of similar votes before, but frustration over the stalled devolution process led some to predict that the balance could finally be tipped in Donaldson's favour.

The Lagan Valley MP was asking members to reject the Joint Declaration on restoring power to the Stormont assembly outright.

Trimble wanted a compromise solution whereby parts of the document are accepted while others are picked out for criticism.

The party leadership was not specifically on the agenda, but had Trimble lost the vote he may have felt his position in the party was untenable.

Donaldson, who opposed the initial Good Friday Agreement in 1998, said Monday's South Belfast meeting was a "defining moment for unionism".

Over the weekend Trimble wrote to council members asking for endorsement of a six-point plan which involves no return to power-sharing without a "real transition to peace and democracy" by republicans.

His amendment to Donaldson's motion asks the council to reaffirm a previous resolution made last September, which demanded an end to paramilitarism as the price of power-sharing with Sinn Fein.

The Joint Declaration from London and Dublin was intended to provide a route map to restoring devolution, suspended in October last year.

Unionists feel it is not tough enough in guaranteeing that the IRA's gives up its weapons before fresh elections can take place to the assembly and a new power-sharing executive be formed.