David Cameron has hailed the agreement achieved by the power-sharing parties at Stormont as a "workable" deal containing the prospect of a brighter, more prosperous future for Northern Ireland.
The Prime Minister led reaction to the political deal hammered out after 11 weeks of talks which included all-night sessions that at several points approached breakdown rather than breakthrough.
After flying back to London 10 days ago, Mr Cameron said the financial underpinning of the deal would mean the parties could begin to overcome the key outstanding issues left unresolved since the 1998 Good Friday Agreement.
"This historic agreement has been long in the making. We will now all work collaboratively to see this through. The people of Northern Ireland deserve nothing less," he said.
Secretary of State Theresa Villiers, who chaired the twice-weekly and then more intensive sessions, said: "It offers us a new start and a far more hopeful future. But it will need continued hard work."
Irish foreign affairs minister Charlie Flanagan said the deal would build "on the hard-won peace on this island".
First Minister Peter Robinson said it was a "very significant" agreement and a "monumental" step forward.
"Of course every one of us would have liked to have had a more comprehensive and complete agreement but this is as much and more than we have ever been able to do on these issues in the past," he said.
Finance Minister Simon Hamilton added: "What we now have is a way forward that will not only see welfare reform proceed with Northern Ireland building on the Great Britain system, but will see a sizeable financial package bolstering the Executive's coffers.
"Around £2billion will be available to the Executive over the coming years that will greatly assist us in preparing for difficult budget times ahead. As too will the cross-party agreement on an ambitious public sector restructuring programme."
Deputy First Minister Martin McGuinness said the deal offered the parties the chance for a "fresh start" with more focus on consensus.
"How we move forward from here has to be different. The Executive has not stood up to those who intend to take us back to the past. I have... and they were those that murdered the soldiers in Antrim, Constable Stephen Carroll, Ronan Kerr and David Black, prison officer.
"There has to be a step change, we have to face down those people. All of us have to rehabilitate the poor image the Executive and Assembly has."
However, Sinn Fein President Gerry Adams said there were "uncompleted commitments" including on the Irish language.
Ulster Unionist Party leader Mike Nesbitt said: "While there were many important issues on the agenda, the only one that posed a real and present threat to the future of devolved government was the finances."
SDLP leader Alasdair McDonnell said he believed the "deal falls short" and that he was disappointed the document was not as comprehensive as he hoped.
Alliance leader David Ford said: "We do have real concerns that some of the issues that prevent us sharing our community have received only partial solutions, or have been entirely passed on to other processes."
TUV leader Jim Allister argued: "Nothing in these proposals does anything to address the fundamental flaws at the heart of the institutions as we remain lumbered with mandatory coalition."