BBC Ireland Correspondent Mark Devenport reports on reaction to the award

World leaders rushed to congratulate republican SDLP leader Mr Hume and his co-winner, the province's First Minister, Ulster Unionist leader David Trimble.

But the radical Democratic Unionist Party called the award a "farce".

Leader Ian Paisley said that without paramilitary arms decommissioning, the award was based on a "phoney peace".

John Hume: Agreement means respect for unionists and republicans

Mr Hume argued that the Nobel prize would bring the unionist and republican communities of Northern Ireland together.

He said: "I hope that now they see the very substantial international goodwill and recognition of their own community, that will strengthen the support for the (Good Friday) Agreement and for implementing the Agreement.

"This is because quite central to this whole Agreement is respect for the identity of both sections of our community.

"The unionist people have always feared that their identity was going to be undermined, but this Agreement, as I've said repeatedly, gives no victory to either side."

BBC Ireland Correspondent Tom Coulter looks at the careers of Trimble and Hume

UK Prime Minister Tony Blair led the tributes to the rival politicians, saying there could be "no more worthy winners".

He said: "This is a recognition of their courage and their qualities of leadership that were so vital in laying the road to peace."

The Norwegian Nobel Committee's citation said: "John Hume has throughout been the clearest and most consistent of Northern Ireland's political leaders in his work for a peaceful solution."

It added: "As the leader of the traditionally predominant party in Northern Ireland, David Trimble showed great political courage when, at a critical stage in the process, he advocated solutions which led to the peace agreement."

John Hume's reaction on hearing the news

Mr Hume has worked tirelessly for a united Ireland since the 1960s while condemning the violence of the Irish Republican Army fighting to end British rule.

About 3,600 people have died in the Troubles over that time.

David Trimble: First Minister of Northern Ireland

Mr Hume and Mr Trimble were major architects of the Good Friday Agreement that has brought new hopes of peace.

The deal, signed in April, seeks to end 30 years of sectarian violence and enshrines a new assembly for the province, of which Mr Trimble is the first leader.

Despite the Real IRA bombing of Omagh in August, when 29 civilians were killed, the peace process has remained on course.

David Trimble: "It's a great honour"

Mr Trimble, welcoming the award on a fund-raising trip to the US, said: "We know that while we have got the makings of a peace, it is not wholly secure yet. I hope it does not turn out to be premature."

He added: "It's an endorsement not just to me personally but to all those who helped to produce the agreement."

Mark Devenport on the controversy surrounding the award

Sinn Fein President Gerry Adams, who was tipped as a possible winner, said the award would be an incentive to the peace process.

The winners of the �570,000 award were announced in Oslo by Francis Sejersted in the ornate Nobel Institute.

Other candidates involved in Northern Ireland included US mediator George Mitchell, UK Northern Ireland Secretary Mo Mowlam, Irish Prime Minister Bertie Ahern and Mr Blair.

Also nominated in a record field of 139 candidates were the UN agencies for work on human rights and the Czech President Vaclav Havel.

For a profile of David Trimble click here

For a profile of John Hume click here

Click here to see a selection of Nobel Prize Laureates.