Tony Blair has signalled his confidence in the Northern Ireland secretary as pressure on her increased following her declaration last week that the IRA ceasefire remained intact.

The Downing Street spokesman also confirmed that Mr Blair was fully consulted before Dr Mowlam's declaration on the state of the IRA ceasefire on Thursday.

Dr Mowlam had not been isolated and was "doing one of the most difficult jobs in government extremely well".

Denis Murray reports on the Unionists' position

She will speak with the prime minister on Tuesday afternoon.

Mr Blair is seeking assurances from the parties that they are committed to the review due to commence on Monday under the chairmanship of former US Senator George Mitchell.

Postponement considered

A postponement of the review was among options considered by the Ulster Unionist Party when they met on Tuesday to discuss tactics in the wake of fresh incidents of paramilitary violence, but no decision was made on the next step to be taken.

The BBC's Carole Walker: "The Prime Minister supports Mo Mowlam's statement"

Party leader David Trimble faces calls from his colleagues to boycott the review and cut off all contact with Sinn Fein.

Unionist anger increased following threats by the IRA to kill six Catholic teenagers unless they leave Northern Ireland.

'Mafia state'

Party leader David Trimble: "Our view is that the government made a mistake"

One option considered during Tuesday's meeting involves the UUP's participation in the review as scheduled - but that inter-party contact with Sinn Fein would not take place between sessions.

After the UUP meeting Mr Trimble referred to recent IRA threats, which have included ordering six teenagers to leave Northern Ireland.

David Trimble: Questions wisdom of holding review in current context

He questioned the commitment of the republican movement to the peace process.

"Nobody is going to agree to live in a 'mafia' state," he said.

A proposed judicial review of Northern Ireland Secretary Mo Mowlam's decision that the IRA has not broken its ceasefire has not been ruled out.

The UUP is expected to meet a number of times over the next few days to decide their strategy in advance of the review.

Ken Maginnis: "We have not seen the end of murder"

Unionists earlier called for Dr Mowlam to resign, saying she was not up to her job.

They are pressing Mr Blair to become involved in talks to try to overcome what they see as a "crisis" in the peace process.

UUP deputy leader John Taylor said he could not recommend his party's participation in the review while republicans continued to kill and expel people from the province.

Progressive Unionist leader David Ervine: "Moderate Unionism is under serious pressure"

"I do not believe we should be participating with Sinn Fein in the review under the present circumstances," he said.

Anti-Agreement UUP dissident, Willie Ross, the MP for East Londonderry, echoed these calls during a speech at a terrorist victims' conference in Portadown on Tuesday.

Sceptical response to arms pledge

Sinn Fein is to decide whether or not to take part in the review on Sunday, the day before it is due to begin.

The escalation in IRA violence comes as the breakaway loyalist paramilitary group, the Loyalist Volunteer Force (LVF), issued a statement promising to handover more arms.

The LVF is the only paramilitary group to have handed over any weapons. It surrendered nine guns and a quantity of ammunition to the International Body on Decommissioning in December.

In a statement the group called on the republican movement to reciprocate by handing over weapons in a ratio of 10 to one.

The statement by the LVF has met with a sceptical response from nationalist and unionist politicians.