The government has engaged in a "cover-up" over claims the IRA has kept some weapons, the DUP has alleged.
Ian Paisley wants a list of what the IRA decommissioned
Party leader Ian Paisley made the claims after meeting the head of the decommissioning body General John de Chastelain on Wednesday.
He called on the security forces to provide more information on claims that some IRA members kept arms.
Mr Paisley demanded the publication of what the IRA decommissioned and estimates of what remains.
"They should tell the people what they know," he said.
"They should tell the people what they know so that the people can be forearmed to meet what is going to happen; because those arms are going to be used against the Protestant population of Northern Ireland."
The meeting followed fresh concerns about the extent of IRA decommissioning after simultaneous reports last month by the Independent Monitoring Commission and arms body.
Both cited intelligence reports from unspecified NI security sources that some IRA members had retained arms.
There have been claims that some IRA members kept guns
Also on Wednesday Sinn Fein chief negotiator Martin McGuinness said the DUP "search for excuses" to not share power had to end.
"This meeting has little to do with IRA weapons," he said.
"The IRA have dealt decisively with that issue and the DUP know this. What this meeting is about is part of the DUP search for excuses not to engage."
SDLP leader Mark Durkan accused Mr Paisley of making "inflammatory comments" after the meeting.
"On the one hand Paisley says that he raised loyalist decommissioning with the IICD," he said.
"Then in the next breath he predicts sectarian warfare and gives them the excuse they need to hold on to their weapons."
It is understood that General de Chastelain will also meet representatives of the Ulster Defence Association later this week to discuss loyalist decommissioning.
January's IMC report said the IRA was still gathering intelligence, primarily for its political strategy.
The body's 8th report said the activity had been authorised by the IRA leadership. It also claimed some IRA members were still involved in organised crime.
However, General de Chastelain said Irish police had no intelligence to support the weapons retention claim and the IRA assured him it was not.
However, Lord John Alderdice of the IMC said he could not share the general's assessment.
The IRA denied the intelligence assessment that it held on to some weapons.