The international decommissioning body has said it is ready to talk directly to republican and loyalist paramilitaries in an attempt to secure a hand-over of weapons during all-party negotiations which begin on Tuesday.
Speaking at a press conference in Belfast yesterday, the body's chairman, Gen John de Chastelain, said it had been given special immunity by the British and Irish governments to meet paramilitary members if necessary.
He challenged the IRA and the Combined Loyalist Military Command to start handing over weapons to help move the peace process forward.
He hoped and expected that weapons would be handed over as the talks process proceeded.
However, he believed total decommissioning would be "the last piece in the jigsaw".
Gen de Chastelain said the hand-over of some weapons would greatly help to build trust between the parties and that he would be working hard to achieve this.
"We will meet with anybody who can help us to move this process forward," he said. "If it is active members of paramilitaries on both sides, of course we will meet with them. We have been granted the immunity to do that."
He also said the decommissioning body would meet representatives of paramilitary organisations and anybody else who could speak authoritatively for them and answer the commission's questions.
"We would expect to see weapons handed over in parallel with the talks," he said. "I don't think it is impossible." It was important that all those taking part in the process, including the paramilitaries, were looking for a peaceful way of handling their differences.
"If they are seeking a democratic way forward they don't need weapons," he said. "If that is the case, and if they are ultimately going to hand them in once a settlement is agreed, why not start while the talks are going on and help reach the settlement?"
Responding to IRA statements that it would not decommission before a final settlement, he said: "One way of helping that movement forward is to show co-operation by handing in weapons." Decommissioning, he stressed, was not intended in any way to express defeat or victory.
"There has been no military defeat, the IRA has not been defeated militarily, neither have the loyalist paramilitaries." Decommissioning would not be an easily achieved objective, he admitted, and the paramilitaries could not be forced to hand over weapons as it had to be a voluntary process.
The other members of the commission are an American diplomat, Mr Donald Johnson, and a retired Finnish Brigadier, Mr Tauno Nieminen. The body is dealing only with illegally-held weapons. The IRA and Sinn Fein have said they want the question of weapons held by the security forces to be addressed.
But Gen de Chastelain said he believed that when no weapons were held outside the law, there would be more relaxed security: "If we can get the illegally-held weapons, there will be less need for legally-held weapons."
He reiterated that any arms handed over would not be forensically tested by the RUC. He also stated that the commission would accept the verifiable destruction of weapons by those who held them. However, it would need to take place to the commission's satisfaction.