The DUP has been holding talks with the two churchmen who witnessed the IRA's final act of decommissioning.
The witnesses said there was no shadow of doubt it happened
The party requested the meeting after questioning the independence of former Methodist President Rev Harold Good and Catholic priest Father Alec Reid.
DUP Upper Bann MP David Simpson, who attended the meeting, said his party was not questioning the integrity of the two churchmen.
However, he said his party still had concerns over what they had seen.
DUP leader Ian Paisley had said the two clergymen were "IRA nominated".
The party pressed the two men about how they were appointed and what they saw, although it remains unclear if they were able to give more details.
The head of the arms decommissioning body, General John de Chastelain, said on Monday that the IRA has put all of its weapons beyond use.
The churchmen said in a statement that "beyond any shadow of doubt, the arms of the IRA have now been decommissioned".
An Ulster Unionist Party delegation also met the church witnesses on Thursday.
UUP deputy leader Danny Kennedy said it was now clear that they had been ready to perform the role of arms witnesses as far back as last November.
This was a month before crunch political talks between the DUP and Sinn Fein collapsed over Ian Paisley's demand for photographic proof of decommissioning.
He said they had gained a "valuable insight" into what the two men had witnessed but his party would wait to assess IRA activity on the ground before reaching a final conclusion.
Mr Paisley's comments on Tuesday were condemned by the Ulster Unionist Party, when Mr Kennedy said it was "a matter of regret" that others from another Christian tradition had chosen to question the churchmen's integrity.
DUP Upper Bann MP David Simpson rejected this, accusing Mr Kennedy of "misrepresenting" the party's position.
"No-one is disputing that the two men are faithfully reporting what they saw. The question is did they see it all?" he said.
After meeting General de Chastelain, Mr Paisley said the witnesses were not appointed by the government or arms body.
The party said the list of IRA weapons had been "revised and tampered with".
"These are the things that put a very big question over what has taken place," said Mr Paisley.
Speaking on Tuesday, Sinn Fein's Gerry Adams said Mr Paisley would need time to digest the move.
"His concern is (about) a process of change and... because he has lived and built a career on frightening people and on crisis," he said.
"The future is going to be good for everyone on this island, so we have to give Ian Paisley a wee bit of space."