The Ulster Unionist Party leader Mr David Trimble has said the Northern Ireland Secretary had no choice but to declare the UDA and LVF ceaseifires had been breached. But he warned Dr Reid he should treat the IRA in the same way.
The North was quiet last night after the announcement yesterday evening.
Dr Reid, advised by the RUC chief constable, Sir Ronnie Flanagan, declared that the UDA had "systematically breached" its ceasefire, which it called seven years ago today.
Dr Reid made his move against the UDA after Thursday night's violence on the Shankill that he said was "clearly orchestrated" by the loyalist group. Dr Reid made the same ruling against the LVF, which two weeks ago murdered Sunday Worldjournalist Martin O'Hagan.
But Mr Trimble told Sky News: "I would like an assurance from Dr Reid that the next time the IRA murders someone he will take the exactly the same action. Because over the courses of the last year the IRA has murdered four people and nothing has been done about it.
"So Dr Reid won't want to look like he is being biased in his approach", Mr Trimble added.
Asked about the prospect of UUP ministers withdrawing from the North's Executive, Mr Trimble confirmed that the ministers would "resign and withdraw" if there is no decommissioning by the IRA.
"I'll give a more precise statement on this on Monday", Mr Trimble added.
Meanwhile there were claims that some loyalist paramilitaries could declare "open season" following the de-recognition of the loyalist ceasefires.
Mr John White, chairman of the Ulster Democratic Party, which speaks for the UDA, said he feared the move might have removed any remaining restraint on individual members of the organisation who were intent on violence.
Mr White said loyalists were still assessing the implications of the move.
Members of the UDA and its sub-grouping, the UFF, who had observed the truce were angered by the development, he said.
"I haven't spoken to anyone with any great hostility - and I don't see that there is going to be that type of reaction," he went on.
"But there are individuals who are going to be saying that if the ceasefire is not on it's almost an open season for them."
Sinn Fein and the SDLP welcomed the announcement. It was expected to be raised at the annual conference today of the PUP, political wing of the outlawed Ulster Volunteer Force. Its ceasefire, declared in 1994 along with that of the UDA, is still recognised.