Unionist hardliner Jeffrey Donaldson has finally severed his connections with David Trimble's Ulster Unionist Party, and will join forces with Ian Paisley's Democratic Unionist Party in next month's review of the 1998 Good Friday Agreement.
``I am not going to give David Trimble and his cronies the joy of throwing me out of the party,'' he declared, referring to last week's heave against him by supporters of the current party leader.
The announcement has ended years of internal feuding among Ulster Unionists. The one-time challenger for the party leadership predicted that if the party did not topple Mr David Trimble as leader, then the UUP faced ``political collapse''.
``If the UUP does not change leader and policy then the DUP will do to the UUP what Sinn Féin is doing to the SDLP,'' he said.
Mr Donaldson said it was a ``sad day''.
``I have been a member of the Ulster Unionist Party ever since I was a teenager,'' he said.
``However, I have come to the conclusion that it is not the party I joined and it has abandoned the principles I believe in.''
In a statement Mr Paisley welcomed the resignations as ``a momentous decision that will deal a hammer blow to the Ulster Unionists''.
Fellow Assembly members Arlene Foster and Norah Beare also resigned with Mr Donaldson. Martin Smyth and David Burnside, two other prominent hardliners in the UUP, are so far remaining within the party.
Mr Donaldson has rules out a return to the UUP and has indicated that he would formally join the DUP.
That would meant that in any new executive, under the d'Hondt system of apportioning posts, the DUP could be entitled to four ministerial positions, compared to only two for each of the three other main parties.
``Unionist realignment is the only option now. Otherwise we could be facing the prospect of Sinn Féin as the largest party after the next Westminster elections,'' said Mr Donaldson.
Since the Good Friday Agreement was signed over five years ago, Mr Donaldson has exerted a uniquely malign influence on the peace process, openly opposing the Agreement and successfully pushing for his party to make increasingly insatiable demands from the IRA.
Some thirteen or fourteen acrimonious meetings of the UUP's ruling Ulster Unionist Council failed to heal the hopeless divisions within the party and frutrated the broader peace process.
Observers believe the resignation could now allow the UUP to coalesce around a clear policy and negotiate in a meaningful way in the upcoming talks. However, the concern now is that the UUP will increasingly be seen as irrelevant as a Donaldson-supported DUP is now clearly the dominant unionist party.