A decision on whether the Ulster Unionist Party will pull out of Northern Ireland's power-sharing executive has been put off until September.

Party leader David Trimble met his assembly members at Stormont on Thursday to discuss the government's statement on paramilitary ceasefires.

Unionists had been calling on the prime minister to place sanctions on Sinn Fein over alleged IRA involvement in terrorist activity.

But on Wednesday, Tony Blair stopped short of sanctions, saying any future breach of loyalist or republican ceasefires would be met with a "rigorous" response.

Unionists have criticised Tony Blair's statement

After the 90 minute meeting at Stormont, Mr Trimble said he would consult with his party in a formal way in September.

The Northern Ireland first minister refused to say whether he would call a meeting of his party's ruling council at that time.

He said his assembly team wanted it on record that they thought the government's statement and conduct was "appalling".

Mr Trimble said the Northern Ireland Secretary, John Reid, had given the impression the paramilitaries had won.

Dr Reid said he was considering using an assessment of levels of paramilitary violence within both loyalist and republican communities to supplement his decisions on ceasefires and would decide on this over the summer.

Tony Blair revisited the subject at the second of his "presidential-style" media briefings in London earlier on Thursday.

He reiterated that the government was prepared to move against Sinn Fein if the IRA ceasefire was breached.

While recognising loyalist violence, Mr Blair said it was Sinn Fein and the republican movement which was sitting in government.

"We are looking carefully, as John Reid said yesterday, at precisely how to give credibility to any assessment. That we have some mechanism to assist us in this process," he said.

Gerry Adams accused government of political bias

Sinn Fein president Gerry Adams said the threat of action from the government was fuelled by political bias.

He was speaking in Dublin after talks with Irish Foreign Minister Brian Cowen on Thursday.

"Mr Blair's statement yesterday named the IRA four times.

"It did not mention the Ulster Defence Association. It did not mention the loyalist groups and all of that was based on bad advice to him by a system that used to pretend there was no such thing as sectarian attacks from loyalists," he said.

"The British Government is not politically neutral on this issue so all of the advice will be to point out the republicans as the people who need to be confronted and it is a big challenge to turn that around."