Ulster Unionist leader David Trimble has announced his resignation as leader of the party, after losing his Westminster seat in Upper Bann.
Mr Trimble said he did not wish to continue in the post which he has held since 1995.
The party lost four of its MPs in the general election, while the DUP's Ian Paisley and Sinn Fein's Gerry Adams won with increased majorities.
What is your reaction to the Mr Trimble's departure? What does it mean for the future of the Northern Ireland peace process?
This debate is now closed. Read a selection of your comments below.
The following comments reflect the balance of opinion we have received so far:
It's sad to see the rejection of the progressive voices of unionism but the British government should have seen it coming. It's no good Blair now paying warm tributes to Trimble. He should have been focussing on Northern Ireland rather than Iraq and supporting Trimble in getting the message across to Sinn Fein that there can be no more concessions or compromises until the IRA decommissions fully and openly and the political party of SF severs itself entirely from anyone who still believes in violence as an option. I sincerely hope Trimble can in time find some kind of arbitration role in the peace process. The thought of Northern Ireland being left in the hands of Ian Paisley and Gerry Adams is a worrying one.
Bruce Acton, Winchester, UK
His departure is long overdue. David's arrogance and unpopular policies have caused the majority of the unionist people to vote elsewhere. This is a democracy and the people have spoken.
David Trimble was a man who was pulled from all sides and fought courageously to reach compromise in a land of bigots and extremists. He was one of the few sane and rational voices who considered all aspects of the situation and followed the course he knew to be right. It seems to me that his departure symbolises everything that is wrong with Northern Ireland, and it further enhances my desire never to return.
Matt, Edinburgh (originally Belfast), UK
Mr Trimble caused his own downfall, having made statements in the past about what he would do and not do and then going back on his word. People in Northern Ireland are not stupid. Mr Blair and his side kicks will now have to listen to the people of Northern Ireland and not try and wipe their eye. Good bye Trimble your day has come to pass.
A sad day for NI. Mr Trimble demonstrated leadership during his many years as First Minister. Leadership meant that he realised that to achieve peace and prosperity for NI then he had to negotiate with nationalist politicians. The DUP has a hard act to follow - like Mr Trimble they too will have to negotiate with other elected national politicians. The sad thing is that moderate politicians have lost out. Let's hope that Mr Trimble can continue with his efforts in the House of Lords. Let's also hope that the DUP become "statesmanlike". Please let Nigel Dodds become leader and get rid of the bigots in the party. Only then can we have some hope for the future. People in the UK are fed up with extremists - DUP be warned.
Liz, Lincoln, UK
Isn't it about time when the man who gave Iraq its democracy, finishes the NI subject that he started all those years ago. Instead of strength there's been nothing but weakness and the usual rhetoric from Blair. Trimble is but another casualty of Blair's failure to grasp the metal. Tough on Iraq but can't handle the real business at home.
Alan, Warsaw, Poland
The polarisation of politics in N Ireland is to be regretted. It is now inevitable that the DUP will work as hard as they can to ensure the IRA are sufficiently irritated to restart the violence in order that Paisley can refuse to work with them and so kill off the idea of sharing power. It's really high time the Westminster government walked away from Ulster and let them work out their own problems. I fail to see why any more of my tax should be spent on this bigoted bunch.
David Trimble is a brave and intelligent man who took the risk of leading unionism into a peace deal with the IRA. His political demise has been as a result of the IRA's slowness to move into proper democracy, the risk backfired, but someone had to take it and I admire him for it.
Ciaran, Belfast, Northern Ireland
Not that I'm a fan of Trimble, but it is disturbing that the vast majority of unionists would rather vote for someone who discriminates against those who do not follow their particular brand of extremism. I'm leaving this place for Australia as soon as I can!
As Northern Ireland once again sinks into anarchy, the only people to blame are the NI voters. No longer will I feel sorry for them. In my view, they have brought the future troubles on themselves.
God help the people of Northern Ireland with David Trimble gone and Ian Paisley gaining even more power I can see the peace process falling flat on its face. Things have gone backwards now not forwards.
Mr Trimble's departure has more to do with Tony Blair's failure to keep his word on issues agreed relating to the GFA. Mr Trimble is a convenient scapegoat. The electorate has reflected that in the voting pattern during the past two elections. How then will Mr Blair attempt to reconcile the two extremes now holding sway?
Tom Gorringe, Armagh
Ian Paisley must be chuckling. Who said those who shout the loudest don't get heard the most? The Northern Ireland electorate can't say they don't deserve what's coming!
Northern Ireland occasionally produces politicians like David Trimble and Gerry Fitt, but unfortunately not often enough, otherwise it would be a far better place.
David Trimble is a prime candidate for a seat in the Upper House. Lets hope he gets offered one and feels he is able to accept.
John Colby, Market Bosworth, UK
David Trimble always came across as a very reasonable man - the acceptable face of Ulster Unionism. Sadly he has been replaced by the DUP, a party led by, in my view, a bigot and hypocrite. I see nothing Christian about Paisley and he should renounce his dog collar. I see no progress towards an enduring peace in Northern Ireland.
Barry, Stone, UK
So, after all the spin and nonsense of the past eight years, we're left where? There've been more "ultimate, final, really the last one" deadlines than I can count, all ignored. I know, let's have some focus groups, make some "serious" TV programmes about some Irish women, that should sort it out by Christmas.
The Brits will figure out a way to stall the process with or without Trimble. However, Paisley and his party will demand more of the Brits and the British government will cave in, because it will suit them. I just hope we don't hear the old tired mantra from the Brits that they have tried everything to get the parties to go forward. I do not believe them. They have interfered for too long in the "plastic" state. It is time that they do something right, for a change, and get out of Ireland.
Margaret Wernerspach, Rockaway, USA
How disappointing to see the usual rose-tinted spectacled American contingent wading in with their usual blinkered prejudice. If Sinn Fein IRA were really interested in peace, they'd have decommissioned their weapons by now, and those on either side are absolutely right to hold out for progress on decommissioning whilst the other side remains intransigent.
Dean, Maidenhead, UK
The recent election result in Northern Ireland is a crushing blow for all moderates and ought to send out a strong message to the British government. I am saddened that the UUP has taken a hammering for lack of Republican progress on the agreement. There are clearly no rewards in politics for those who seek to move forward - the UUP have been poorly rewarded for their acts of trust and compromise. My only consolation is that the UUP still has one incredibly competent and hard-working MP. I wish her success as she stands alone at Westminster. I think David Trimble has been long aware that he risked sacrificing his political career in the interests of peace. he should be commended for that and I have no doubt he will be absolved by history.
Jenny, Oxford, UK
Trimble was smart enough to see that old unionism couldn't continue - it seems the unionist electorate hasn't come to that conclusion yet. But at least Trimble will have the last laugh seeing the DUP have to eat its words.
Danny, Sydney Australia
Very sad day for Northern Ireland and Trimble. Unlike Paisley and his men, Trimble showed leadership by offering Unionists an alternative vision, rather than the tired old rhetoric offered by the hardliners. People need to realise that Paisley and co. do nothing other than blame others. People have voted for the return of immature polarised politics.
Steve, Ballymoney, NI
God help Ireland - I see serious trouble ahead, as the Nationalist bigots will confront the Unionist bigots, both sides will refuse to talk, and will return to violence and the barricades. Time for Blair to show us what he's made of.
John, London UK
An honourable man who offered Adams a deal that Adams should have accepted. Adams has already found that in Paisley, the direct beneficiary of his failure to do a deal with Trimble, he has an opponent who is more even more adept at brinkmanship than he is himself! Good luck Gerry, dealing with Paisley is gonna be tough.
Martin Smith, London
Mr. Trimble made a huge mistake. He trusted both the Labour government and Sinn Fein. Sinn Fein has never had any intention to disarm. The victims will continue to be the families of both sides terrorized by gangsters.
Carlos Cortiglia, London, United Kingdom
It used to said that the ordinary people of Northern Ireland had no time for extremism and only wished to live together in harmony. The fact that they voted in such numbers for Sinn Fein and the DUP shows what rubbish that was.
I am glad that he has departed. He was a blackmailer and a moaner. By signing the GFA, he agreed to Decommissioning under the direction of the GFA. But like the rest of those Orange boys, that acceptance did not last very long. If he and the UUP really gave the agreement a chance, then he would be in a good position today. But no, he had to keep blackmailing the Civil Rights Party of Sinn Fein with weapons talk, time and time again.
Patrick Walsh, Boston, USA
Inevitable that Mr Trimble would go. The party tried to make the Peace work but the intransigence of Sinn Fein made them look weak in Unionist eyes. The DUP filled the vacuum and the UUP is no longer relevant. I fear for the future of NI without his compromise efforts.
Jim Kirk, Basildon UK
It doesn't make any difference to me because Tony Blair and his Labour Party has won again with a reduced majority. Any losers and winners by the opposition would make little difference since what Tony Blair has planned for the future will go ahead without them.
It is clear that the NI electorate have had enough of moderate politics, but I suspect that the control of Sinn Fein lies south of the border and that this is where the next move must come from. I suspect the sticking point of the verification of disarmament has an economic cause. The IRA want to sell their arms and verification would prevent this. If both governments gave all sides an ultimatum backed by sanctions something could happen.
Tony, Welling Kent
Mr Trimble's departure is a sad loss for Northern Ireland. We now have the Republican and Unionist hard men on the ascendancy, whilst Tony Blair continues to appease the IRA from London. God help you all......
David, Milton Keynes, UK
His leadership has been on a knife edge for the last few years. No one in Northern Ireland should be surprised by his party's failure in the elections of Trimble's demise. Unionists here have woken up to his lies and went with a party they can trust to keep their word.
Scott, Londonderry, NI
Very sad at Mr Trimble's departure. His was an almost lone voice of common sense and Northern Ireland politics will be the poorer for his departure.
Sally Roberts, London, UK
David Trimble was a hardline Unionist who also happened to be a pathetically weak leader. He offered nothing but the same old tired rhetoric which the moderate people of Northern Ireland are fed up hearing. He can now cash in his Nobel Peace Prize (which he never deserved in the first place) and fund his and Daphne's long overdue retirement. Good riddance.
Let it be a warning to all fools who get conned!
Steve Donnelly, Cookstown, N Ireland