The Progressive Unionist Party's chief spokesman, Mr David Ervine, has said the Belfast Agreement is the only means of ensuring the North does not slide back into conflict.
Addressing the PUP's annual conference in east Belfast on Saturday, Mr Ervine said he believed a deal was possible on decommissioning and urged all the North's political leaders to concentrate their efforts to reach a compromise.
"In a divided society, risks must be taken by both sides. It is imperative that each side be sure the other is as prepared to stretch their own community as much as the other negotiator is.
"I've heard it called a leap of faith. I've heard it portrayed as taking the high moral ground. In truth, what it needs to be about is rational thought and doing the honourable thing. We hear much of what people cannot do.
"When are we going to hear what they can do? Reaffirming a community's own fears is not politics. When are we going to hear the leaders of nationalism and republicanism state that unionism does want a Fenian about the place?
"When are we going to hear the leaders of unionism state that they know the retention of illegal weapons is not for tactical future use?
"These are assertions that, if utterable, could adjust the whole perspective of debate about the implementation of the process of devolution."
Mr Ervine called on the Provisional IRA to be honest about its intentions and stop issuing vague, ambiguous statements.
"The Provos must be aware that once the agreement's structures begin to function, the only potential for sabre-rattling and rumbling in the undergrowth might be to get Bairbre de Brun a larger share of the ministerial budget."
He accused anti-agreement unionists of making "pathetic, childish and petulant outbursts that were simply yesterday's arguments". He added: "If Ian Paisley managed Manchester United, on the basis of his victories to date, they would be playing non-league Sunday-morning park soccer."
He warned that the two governments would impose their own settlement if the agreement failed. The agreement was a "worthy prize" which offered an end to the Republic's constitutional claim over the North. The peace process had saved many lives.