The DUP has said it is time the British government recognised that the Belfast Agreement will not work as three-quarters of the unionist community oppose it.
The party's deputy leader, Mr Peter Robinson, said: "The Good Friday agreement is no longer an agreement that has any credibility. It doesn't have the support within the community to take it forward. If any agreement is to stick in Northern Ireland it needs to have the support of the unionist community."
He said the British government also had to recognise that unionists opposed the Patten proposals on policing and that Mr David Trimble could barely muster the support of half his party.
The "irreconcilable differences" within the UUP meant it was no longer a party, and he urged Mr Trimble's internal opponents to leave and realign themselves with other anti-agreement unionists.
However, the UUP deputy leader, Mr John Taylor, denied there was a split in the party, saying it was merely a "difference of opinion in policy".
He said members should now rally around Mr Trimble and support party policy. The onus was on Sinn Fein to convince the Provisional IRA to give up its weapons by May 22nd, otherwise the UUP would have to consider other ways forward.
The UUP assembly party held its weekly meeting at Stormont yesterday. Sir Reg Empey said Mr Trimble had received a "positive reception".
The UUP leader also held talks with the Northern Secretary, Mr Peter Mandelson, at Stormont. He left the meeting last night without comment.
Meanwhile, Mr Mandelson, speaking in Belfast yesterday, said Northern Ireland would become a "byword for political failure" unless unionists and Sinn Fein could make the Belfast Agreement work.
He said the vast majority of people in the North still wanted the agreement implemented. He repeated his criticism of the UUP for linking the name of the RUC to re-entering the executive. This link was "inappropriate", creating the impression that the RUC was aligned with one political party.
Mr Mandelson said: "We are faced with a choice. We either implement the agreement broadly as it is or we just face many years of continued stalemate, of impasse."
Sinn Fein MP Mr Martin McGuinness challenged Mr Mandelson to act to save the peace process. "The next step must come from the British government. They are the key people in all this. They are the people who must make it absolutely clear to the rejectionist unionists that they are not going to destroy all the work we have been engaged in over the past 10 years."
He said his party would do everything it could to help the process. "We want the Good Friday agreement to be brought back out of the wastepaper bin and we are prepared to do whatever we can to ensure success."
He said the UUP's decision last weekend proved that decommissioning was not the problem. "The reality is that these people don't want a Catholic about the place. They don't want to share power. They don't want an all-Ireland ministerial council. They don't want a new policing service.
"They don't want prisoner releases. They don't want justice, equality and human rights for the nationalist people. That is the message they are sending us."