The IRA is discussing giving up 200 tons of its weapons, according to security sources. The revelation comes as Tony Blair and his Irish counterpart, Bertie Ahern, head to Belfast for renewed negotiations.

A joint declaration from the two governments could set out a "peace package" for the parties to sign up to, but negotiations could go on for 48 hours as they try to conclude a deal.

If the IRA announces that its war is over and that there will be a complete end to military activities, the Ulster Unionist Party could accept having Sinn Fein back in a power-sharing government.

Tony Blair is also ready to agree to troop withdrawals, the demolition of army watchtowers in South Armagh, and a possible form of amnesty for terrorists on the run.

Sinn Fein's chief negotiator, Martin McGuinness, told republicans in South Armagh yesterday: "It has not been an easy negotiation. It has only moved into a higher gear in recent weeks."