Sinn Fein's Martin McGuinness has said he believes the Northern Ireland First minister will collapse the province's power-sharing executive before next year's assembly elections.

The Mid-Ulster MP was speaking in advance of a statement by the Prime Minister on the status of paramilitary ceasefires, expected on Wednesday.

"It is increasingly unlikely that we are going to get to the elections of next May," he told the Irish Republic's state broadcaster RTE on Sunday.

"In all probability the leadership of the Ulster Unionist Party have already decided that it is much better to go quicker and on a very anti-Sinn Fein agenda.

Tony Blair: Pledged to rebuild confidence in the process

"We are here for the long haul and the sooner David Trimble and Ian Paisley recognise that the better."

Meanwhile, David Trimble has said the Prime Minister Tony Blair must prove he is the guardian of the peace process by bringing pressure to bear on republican paramilitaries to implement an unambiguous cease-fire.

Speaking on BBC's Breakfast with Frost programme on Sunday, Mr Trimble said the IRA's apology last week for civilians killed in the Bloody Friday bombings did not reflect the actions of republicans over the last couple of months, when he said they were involved in violence in Belfast.

The prime minister is expected to make a statement on the peace process before the Commons rise for the summer recess on Wednesday.

Mr Blair pledged to rebuild confidence in the Northern Ireland process after talks with the pro-Agreement parties and Irish premier Bertie Ahern at Hillsborough Castle, County Down, earlier this month.

Bertie Ahern: Warned Mr Blair against creating "unnecessary crisis"

It is not clear exactly what Mr Blair intends to do, to show that the government is taking a tougher line on paramilitaries.

However, Mr Ahern has warned Mr Blair against creating "unnecessary crisis" by satisfying unionist demands to remove Sinn Fein.

The Ulster Unionist leadership wants the government to acknowledge there is a law and order problem, involving both loyalist and republican paramilitaries.

Ulster Unionists are also demanding that Sinn Fein, as members of the power-sharing executive, be held to account for any breaches of the IRA ceasefire.

However, Sinn Fein said the crisis was not in the Agreement but within unionism itself.