The Ulster Unionist Party is holding private talks about the future of its leader, David Trimble, after its humiliation in the general election.
David Trimble said he would discuss his future with colleagues
The UUP lost four of its five MPs, including Mr Trimble's Upper Bann seat.
It fell from being the second largest NI party at Westminster, to having just one seat. The DUP has nine, Sinn Fein has five and the SDLP has three.
However, Mr Trimble said he would not stand down over the weekend. "I'm going to consult with colleagues," he said.
"There is a collective leadership of the Ulster Unionist Party, we will come to a consensus about the way forward and take it from there."
Mr Trimble told the BBC's Today programme: "The basic underlying cause is that the republican movement have not behaved properly over the years.
"They have not themselves implemented the Good Friday Agreement. If they had, then they would have disarmed completely in May 2000, that is what they undertook to do, that is what they failed to do.
"Rather than implement the agreement, the republican movement have exploited the agreement. The net result of all of that is that there is total disgust in the unionist community with them.
"That is the basic underlying factor. A contributory factor is that the government, which ought to have upheld the agreement and policed the agreement, has been far too indulgent to republicans."
In a statement on Friday night, UUP chairman James Cooper, said the party was "bitterly disappointed" at the election results.
"It raises a number of questions at a strategic and political level within the party that we will reflect on over the course of this weekend and in the months ahead as we seeks to rebuild trust," he said.
Elsewhere, William McCrea and Sammy Wilson, both DUP, took the South and East Antrim seats respectively from the UUP.
Peter Robinson of the DUP retained East Belfast, while party colleagues Nigel Dodds, Gregory Campbell, Iris Robinson, Jeffrey Donaldson retained their seats, along with leader Ian Paisley.
SDLP leader Mark Durkan won Foyle - a seat held by John Hume since 1983, while his deputy Alasdair McDonnell had a surprise win in South Belfast, taking the seat from the UUP. Eddie McGrady won the party's third seat in South Down
The SDLP lost its Newry and Armagh seat to Sinn Fein's Conor Murphy. The seat had been held by former deputy leader Seamus Mallon since 1986.
In Mid Ulster, Martin McGuinness, Sinn Fein, retained his seat, as did party president Gerry Adams, West Belfast, Michelle Gildernew, Fermanagh/South Tyrone and Pat Doherty, West Tyrone.
Meanwhile, Friday's cabinet reshuffle saw Peter Hain replace Paul Murphy as Northern Ireland Secretary. Mr Hain will also retain his post as Wales Office Secretary.