The Ulster Unionist leader has warned against any rapid devolution of policing and justice powers to Stormont, blaming republicans for the absence of trust needed to end direct rule.
Mr David Trimble said yesterday there was insufficient confidence among unionists for the restoration of devolved government involving Sinn Féin, even in the event of significant "acts of completion" by the IRA, as demanded by Mr Tony Blair.
He branded as "a sop to Sinn Féin" amendments to policing legislation due to go before the Commons next week, which will allow former paramilitary prisoners to serve on local police consultation bodies.
The former first minister, speaking in Strabane, Co Tyrone, on Thursday night, said: "Republicans must realise that the immediate post-agreement optimism cannot be easily rekindled. After the events and revelations of the last year, it will never be glad morning again."
Yesterday he denied there had been an about-turn on unionist devolution policy. He stood by earlier commitments to devolution and the transfer of policing and justice powers but added that allegations of an IRA spy ring at Stormont had dented unionist confidence so much that early consideration of such a proposal was premature.
"There is no point in pretending there isn't a problem," he said. "The way republicans have behaved has created a huge problem for everybody else in the process. This increases the need for them to show clearly to society they have changed."
Earlier this week, Mr Trimble criticised both governments for legal moves to ensure the continuation of the cross-Border bodies in the absence of the devolved institutions.
Yesterday's warning to London and Dublin was in a similar vein.
He told the BBC: "In principle, we are in favour of the devolution of policing and justice and it will be the mark of the coming of age of our institutions here.
"But who thinks our institutions are about to come of age when we have just had one of the participants in it discovered not to be playing the game but to be involved in a huge spy ring?"
He added: "The first challenge is for republicans to reform, to do that speedily, and then perhaps we can get back on track."
Sinn Féin reacted with dismay while the SDLP called on Mr Trimble to "prove consistency" on policing and justice policy.
Mr Martin McGuinness said: "I think that this contribution of David Trimble is yet another unfortunate and unhelpful contribution at this time. All of us need to be very sensible and recognise we are playing for big stakes here, that this is about the future peace and prosperity of our country."
SDLP leader Mr Mark Durkan accused the UUP of policy drift. "In too many people's eyes the Ulster Unionist Party display about as much consistency of position and direction as pinball." He said all parties should work together with a single long-term aim of achieving devolution of powers including justice and policing."
The British and Irish governments yesterday completed the latest round of talks in Belfast aimed as restoring devolution. Junior ministers Mr Tom Kitt and Mr Des Browne said they were encouraged by the "sense of urgency and engagement" by all the parties involved.