The Provisional IRA has drawn up an inventory of its weapons which it may present to the international body on decommissioning chaired by Gen John de Chastelain, according to reliable republican sources.
The sources said the Provisionals had visited arms dumps on both sides of the Border in recent months to compile a list of the weapons they possessed.
It is understood the inventory will be presented to Gen de Chastelain if the peace process unfolds to the satisfaction of the Sinn Fein and Provisional IRA leadership.
This would involve Mr David Trimble accepting Sinn Fein ministers into the new executive before actual decommissioning began, and the full implementation of the Belfast Agreement. It is understood the Provisionals would not be prepared to act under any other circumstances.
The sources also said the Provisionals would never hand over arms to the authorities. If they were to decommission, they would destroy their own weapons.
Their favoured option, in the event of decommissioning, was to take Gen de Chastelain, or one of his representatives, to an arms dump, allow him to inspect it, then concrete over it in his presence. A Catholic priest closely associated with the peace process and a Protestant cleric might also be invited to act as independent witnesses.
This was the option which would least antagonise the republican base, the sources said. Decommissioning was a very sensitive issue for the Provisionals, and any direct arms hand-over to the authorities would be unpalatable for their grassroots, they added.
Provisional IRA members both North and South have been briefed that any comments or pledges by Sinn Fein leaders on decommissioning are irrelevant and that the IRA has currently no policy to decommission.
But the sources said Provisional IRA leaders were not opposed to the principle of "making a gesture" on the issue. The gesture would not be described by the leadership as decommissioning but portrayed as a voluntary action to show the Provisionals' goodwill.
However, the sources stressed that no firm plans had been drawn up on the matter, and much depended on the Ulster Unionists' final reaction to the two governments' Way Forward document.
The sources also said there were no circumstances under which the Provisionals would destroy all their weapons. Any gesture would be a token one.
The leadership knew resignations were inevitable after decommissioning, the sources said. They believed they could retain the loyalty of 65 to 70 per cent of current members. However, there were serious problems in rural areas, especially south Armagh where many activists were totally opposed to any decommissioning.
The sources said it was impossible to estimate how many activists there would simply walk away from any political involvement and how many would seek to join dissident groups.