Two key Ulster Unionist meetings will take place over the next 48 hours to discuss the party's policy on policing and returning to government with Sinn Fein.
The 14-strong officer board will gather at party headquarters in Belfast this afternoon. Tomorrow the 120-member executive will discuss current political developments.
The meetings follow the return from holidays of the party leader, Mr David Trimble, who last night gave his first public statement on the arrests of three Irishmen in Colombia.
The Upper Bann MP told the BBC the arrests of the three for using illegal documentation and allegedly training FARC rebels had damaged Sinn Fein and the IRA's credibility in the eyes of those who were "prepared to give them the time and opportunity to prove their sincerity . . . What that does is destroy their credibility.
"The mountain that republicans have to climb will now be greater. I hope that they will concentrate on that instead of coming out with the sort of puerile statements they have made."
Mr Trimble last night indicated he would be prepared to nominate members to the Police Board once he received clarification from the British government on several issues.
Anti-agreement unionists will argue in favour of supporting a DUP motion in the Assembly to oust Sinn Fein from government and they will also voice their opposition to nominating members to the Police Board until the British government makes concessions to unionists on the new police force.
Sources said they believed the pro-agreement wing would attempt to defer the decision on nomination. Both sides said they did not know if votes would be taken at the meetings and agreed that the issues of policing and sharing power with Sinn Fein could still remain unresolved after the weekend.
UUP MP Mr Jeffrey Donaldson and the honorary secretary, Ms Arlene Foster, will both argue against nominating. Ms Foster said: "There is no need for us to be rushing into any hasty decision. The SDLP held up the process for months until they secured 95 changes to the policing implementation plan and now they are prepared to go on to the board.
"We are being told we are supposed to move. Let us take a leaf out of the SDLP book. Our community has a number of concerns. Let us take the time available to have those addressed."
However, Mr Trimble said his party would accept responsibility and live up to its manifesto commitments on policing when the time was right. It would make nominations to the board at an appropriate point.
The UUP Assembly team met yesterday but did not make any decision on policing. The pro-agreement party chairman, Mr James Cooper, said signing up to the board would provide the opportunity to significantly influence its decisions. "There has been a lot of nonsense talked about the fact that by refusing to nominate we can possibly reverse many of the proposals in the implementation plan.
"The truth is that with serious and significant unionist representation on the board, the board itself will be responsible for the speed and the way the implementation plan moves forward."
He called for a balanced debate on policing in the party over the coming days but insisted the decision on nominations should not be "strung out".
The DUP has called for a joint unionist strategy in opposing the policing reforms, but Mr Cooper claimed its motives were selfish. "Unionist unity, in DUP terms, means the destruction of the UUP and a return to deeply polarised politics."
However, DUP MP Mr Gregory Campbell insisted that his party's motives were sincere.
"The SDLP and Sinn Fein for many months argued and debated and met with the government because the implementation plan wasn't something that they could find themselves in agreement with. They secured changes. We are saying: `Here is a chance for unionists to do the same'.
"By standing together and refusing to nominate to the board we have an opportunity to claw back some of the concessions made to nationalists."