Anti-agreement parties in Northern Ireland have expressed their satisfaction at yesterday's events at Stormont, claiming democracy had prevailed.
The leader of the Democratic Unionist Party, the Rev Ian Paisley, described it as a "good day for Northern Ireland".
He added: "Democracy has triumphed. I am pleased we are not going to have terrorists in the government of Northern Ireland. They have said they are not going to decommission their weapons. You cannot have a democracy and have terrorists in the government."
He claimed the political process had benefited from "bringing down those who want to be in government but are not prepared to give up violence".
Dr Paisley claimed the unionist majority had voted for this outcome by giving him the biggest vote in the June European election, when he stood on an anti-agreement platform.
He said the British government should now go "back the drawing board" and consider introducing a majority parliamentary system in Northern Ireland on a par with that in Scotland and Wales, rather than power-sharing.
He said there should have been a debate in the Assembly on decommissioning, but said the Assembly had been "muzzled" by Mr Mallon and Mr Trimble's actions. "Everybody is discussing the matter of decommissioning. Where better to discuss it than in the presence of Sinn Fein, where they have the opportunity to put their case and where they can have their case rebutted by unionist arguments for all the world to hear."
Mr Paisley's colleague, the DUP Assembly member for East Belfast, Mr Peter Robinson, said Mr Trimble was now "reeling back" from the agreement.
"What has become very clear over the last few months is that people have realised they were conned by the Good Friday agreement, that the pledges made by David Trimble and Tony Blair were not being lived up to, that Sinn Fein was getting into government, that the prisoners were being released. People have recoiled from the agreement and Mr Trimble has at last recognised that," Mr Robinson said.
He added: "The Secretary of State must recognise that the agreement was not implemented because it contained fundamental flaws. Therefore, we now have to deal with those fundamental flaws, which were demonstrated to us in full technicolour today."
The leader of the UK Unionists, Mr Bob McCartney, said that as a democrat he was not willing to share power with those who "did not know the meaning of the word democracy". He felt a "touch of sadness" at the resignation of Mr Mallon. "There are many things I do not share with him, but I take no joy from his resignation." He went on to criticise speeches by the Sinn Fein president, Mr Gerry Adams and the PUP leader, Mr David Ervine. "I take no lessons from such people about democracy," he added.
His former party colleagues, who broke away to form the Northern Ireland Unionist Party some months ago, said their position on the Belfast Agreement had been "fully vindicated".
A party statement said the unionist electorate could "take heart from the fact that our analysis has proved accurate and, more importantly, that a line has been held for democracy".
While the party shared ordinary people's frustration at yesterday's developments, the failure of Sinn Fein to enter government without prior decommissioning presented everyone with a "unique opportunity to embrace a new start built upon a firm foundation of the rule of law and soundly based on the unsullied principles of democracy", the statement continued.
An NIUP member, Mr Cedric Wilson, insisted the position of anti-agreement unionists was entirely justified. He added: "I trust the message leaving Stormont and going out across the world is not unionists' refusal to share power with Roman Catholics and nationalists. It is their refusal to have in government those who have terrorised this community and who are unreconstructed terrorists."
Mr Wilson said democracy continued in Scotland and Wales because people there were not faced with the choice of having to admit terrorists into their governments.
He criticised what he described as the "unholy alliance" between the SDLP and Sinn Fein and claimed that his party's manifesto had predicted the demise of the Belfast Agreement.
The independent anti-agreement Unionist, Mr Fraser Agnew, who represents the United Unionist Party, spoke of "serial killers in government" and claimed Sinn Fein was intent on bringing down the Assembly once the cross-Border bodies were in place. He added: "This is not about being anti-Catholic. It is a fact that all those people have blood on their hands."
The Irish Republican Socialist Party has called on the North's nationalist population "not to react angrily and emotionally at the unionists' machinations over the Good Friday agreement".
"We furthermore call for the signing of a non-aggression pact between the representatives of all armed groups to ensure that in the present political impasse violence does not return to the streets," the IRSP statement added.