The DUP has accused the Independent International Commission on Decommissioning of being a pawn of the IRA and of the Irish and British governments.
After meeting the head of the commission, Gen John de Chastelain, Dr Ian Paisley said no one was convinced either by the IRA's ceasefire or by "any supposed offer they may have made to the general on decommissioning".
He said: "The general is here in anticipation that he will have to meet with the IRA. The fact is that he and the decommissioning body are nothing more than a pawn being used by the IRA and the two governments.
"It is about time that he and his organisation had some selfrespect and tell the [British] government that they are no longer going to be used in this cynical game," Dr Paisley said.
"Our delegation expressed amazement that the truth of the matter is that if P. O'Neill [the IRA nom de plume] turned up again at de Chastelain's headquarters and presented the same offer as before it would not cause either the general or the IRA any embarrassment whatsoever."
Meanwhile, a DUP delegation met US officials to discuss the arrest of the three Irishmen in Colombia.
A party spokesman said: "We in the DUP are determined that the American government will hear the truth about Sinn Fein/ IRA and their continuing involvement in terrorism."