Political leaders, North and South, today paid tribute to Mr John Hume who announced he is to step down as SDLP leader.
Taoiseach Mr Ahern paid tribute to Mr Hume's commitment to finding a political solution to the problems of Northern Ireland. He said the name of John Hume became synonymous with the refusal to yield to the forces of hatred.
Ulster Unionist leader Mr Trimble said: "While we have approached the problem facing Northern Ireland from different perspectives, I have never doubted the sincerity of John's ceaseless efforts to find an agreed resolution.
"At all times, John's voice had been heard because it was never tainted by any covert regard for violence.
"He deserves credit for his work to redefine Irish nationalism and move it away from simplistic territorial certainties and instead to concentrate on people rather than land and on seeking agreement between the people who actually inhabit the land in question," Mr Trimble said.
"This redefinition is consistent with the principle of consent and so created a space where dialogue between unionists and nationalists became possible.
"John's resignation will sadden his many followers but it should come as a relief too to those closest to him who have seen the effect his workload has taken on his health in recent years. I hope, nonetheless, that his is a counsel that we all in Northern Ireland, can call upon in the difficult days ahead," he said.
"May I take this opportunity to wish John and his wife, Pat, every good wish for the future".
Foreign Minister Mr Cowen said Mr Hume had seen the Irish people through some of the darkest periods in their history. "When many had cause to despair, he was a constant beacon of hope, a light in the darkness. He gave us courage and he gave us hope.
"As he steps down, while there are still difficulties to be overcome, we stand closer than ever before to the achievement of a just and lasting peace on this island and to an historic reconciliation between all of the people that share it".
Labour Party leader Mr Ruairí Quinn said the departure of Mr Hume meant that an era in Irish politics and Irish life was over.
He said: "The fact that we have come so far in the peace process is a testament to the tenacity and the commitment of John Hume and the SDLP. Irish people owe John a deep debt of gratitude".
Fine Gael leader Mr Michael Noonan said Mr Hume had made an outstanding contribution not just to politics in Northern Ireland but to the politics of Ireland as a whole.
Mr Hume is the second leader of a Northern Ireland party to resign in the last fortnight. Mr Sean Neeson recently stood down as leader of the cross-community Alliance Party.