Politicians in Northern Ireland cannot continue to cite fears over IRA terrorism as a reason for not joining a power-sharing government for much longer, Northern Ireland Secretary Peter Hain said yesterday.
However, he was accused by the DUP of ignoring IRA criminality.
In what is likely to be seen as a shot across unionist bows, Mr Hain added that Northern Ireland was "light years away" from where it had been.
Republicans were increasingly heading towards engagement in democratic politics, he said.
Speaking ahead of this week's publication of the latest Independent Monitoring Committee report, Mr Hain told GMTV's Sunday Programme that the IRA was "cracking down" on criminal activity.
He admitted that there were still problems with dissidents as well as loyalist paramilitaries.
"But the overall picture is of a Northern Ireland light years away from where it was," he said.
"I don't think that any politician in Northern Ireland can use the excuse for much longer that the IRA poses a terrorist threat . . . as a reason not to join in a power-sharing government over the coming period."
He acknowledged DUP leader the Rev Ian Paisley's desire to ensure that the rug is not pulled from under the party's feet if they get into power-sharing.
But he added: "I think all the signs are, and all the evidence is, that now the momentum and the direction of where republicans are going is overwhelmingly to engage in democratic politics."
Asked whether November would herald a new era of power-sharing, Mr Hain said it was for the politicians to decide.
"They have to ask themselves a question: what is the future of democratic politics in Northern Ireland if they will not exercise the responsibilities for which they were elected?" he asked.
"It's up to them. We can't continue as we are and we won't." The deadline would not be extended, Mr Hain added, and the DUP had a "historic destiny" to take their place. However, Mr Hain's comments angered the DUP's Jim Allister, who claimed they indicated the British government was prepared to turn a blind eye to IRA criminal activity.
The issue was not just about direct IRA violence, it was about attaining an irreversible end to its activities, Mr Allister said.