Politicians who played key roles at various junctures in Northern Ireland’s arduous peace process have paid tribute to David Trimble’s efforts to end the bloodshed.

Former prime minister Sir Tony Blair said his contribution was “immense, unforgettable and frankly irreplaceable”.

Sir Tony’s predecessor Sir John Major praised Trimble’s “critical” role in peace building, while ex-Irish premier Bertie Ahern described him as a “courageous” leader.

Ex-Sinn Fein president Gerry Adams thanked him for helping to get the Good Friday Agreement over the line in 1998.

Sir Tony said: “David Trimble, in his support of the peace process, showed politics at its very best.

“When some within his own ranks were opposed to the Belfast/Good Friday Agreement, he supported it. When we needed his willingness to go the extra mile for peace, he travelled that mile. When there was the prospect of collapse of the process without strong leadership, he provided that leadership.

“His contribution to Northern Ireland and to the United Kingdom was immense, unforgettable and frankly irreplaceable.”

Former Conservative PM Sir John said: “When David Trimble became leader of the Ulster Unionist Party, he made a critical contribution to the Northern Ireland peace process.

“He shed his former opposition to the process, and became an innovative advocate for a peaceful settlement.

“This was a brave and principled change of policy, and critical to the creation of peace in Northern Ireland.

“He thoroughly merits an honourable place amongst peacemakers.”

Mr Ahern said: “He was a courageous man and I had many a row with him and many arguments.. and in more recent years we’ve had good laughs about those debates. But he was tough.

“As a good negotiator I think when he made the deal, when he settled something, he stuck by it. Subsequently he paid the price. And in spite of the horrendous problems that he was under from within his own party and from outside the wider Unionist group, in that last week of the Good Friday agreement he stuck by it.

“He got a lot of criticism from the wider unionist family but you know, I have great admiration for him.”

Speaking to RTE, Mr Ahern recalled his first visit to the unionist headquarters with Mr Trimble on Glengall Street in Belfast in 1995: “That day, we said, listen, should we give this a try? If it works, it’s good. If it doesn’t, you know, let’s not fall out too much.

“I never fell out with him: fought with him, rowed with him and argued with him. But I think we had the one determination: that we would end violence in Northern Ireland.”

Mr Adams expressed his “deep regret” at Lord Trimble’s passing.

“David faced huge challenges when he led the Ulster Unionist Party in the Good Friday Agreement negotiations and persuaded his party to sign on for it. It is to his credit that he supported that Agreement. I thank him for that,” he said.

“In the years immediately following the Agreement I met David many times. Our conversations were not always easy but we made progress. We used to meet quite often on our own and I got to know him quite well. While we held fundamentally different political opinions on the way forward nonetheless I believe he was committed to making the peace process work.

“David’s contribution to the Good Friday Agreement and to the quarter century of relative peace that followed cannot be underestimated.”

Former Northern Ireland secretary Lord Peter Mandelson said: “David Trimble not only took on the Herculean task of negotiating the Good Friday Agreement on behalf of unionists but went through all the pain and strife of implementing it.

“Throughout, he faced unending onslaught from people in his own community – I know because we faced many of these audiences together – and ultimately he didn’t buckle. He was a courageous man who has earned his place in history.”