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A high-stakes plan for breaking a yearlong deadlock in Northern Ireland (search) peacemaking started to fall apart Tuesday as Protestants rejected a new Irish Republican Army (search) disarmament move as too vague.

Britain launched a day of diplomatic drama by confirming that an election for Northern Ireland's legislature — the intended bedrock of the 1998 peace accord here — would proceed Nov. 26. The IRA-linked Sinn Fein (search) party welcomed the move, and the IRA speedily escorted disarmament chiefs to a secret weapons dump.

But hopes of building momentum toward a revival of Catholic-Protestant power-sharing in Northern Ireland were quickly dashed as Ulster Unionist Party (search) leader David Trimble (search) rejected the IRA disarmament move as too shrouded in secrecy.

Trimble — whose British Protestant party is refusing to resume cooperation with Sinn Fein until the IRA ceases to be a threat to Northern Ireland stability — demanded a clear list of weaponry "decommissioned," the method of their disposal, and an IRA commitment to disarm fully in time.

The prime ministers of Britain and Ireland, Tony Blair and Bertie Ahern (search), conceded the Ulster Unionists' rejection of the IRA move was a serious setback to their efforts to build positive momentum and restore power-sharing, the central goal of the 1998 Good Friday peace accord (search).

But the two leaders, who gathered together at Hillsborough Castle outside Belfast, said they would remain there overnight in hopes of resolving the latest confrontation between the Ulster Unionists and the Sinn Fein-IRA movement.

"I hope we can find a way through this, but it's going to take a bit of time," said Blair, standing beside Ahern. "We are very, very close to what could be a quite historic day for Northern Ireland."

"It's a very obvious position that David Trimble has raised, and we now have to see if we can overcome it," Ahern said. "The resolution to that isn't so obvious."

John de Chastelain, the retired Canadian general overseeing disarmament in Northern Ireland, confirmed he had overseen the removal of a substantial amount of IRA weaponry, including automatic weapons and explosives, at a secret location Tuesday.

De Chastelain said the amount of weaponry "decommissioned" — a term used to conceal the method of taking them out of commission — was greater than the volume of weaponry offered by the IRA during two previous disarmament acts in October 2001 and April 2002.

But de Chastelain said the IRA had ordered him not to reveal any specifics about the type or volume of weapons handled. Trimble called that level of secrecy a deal-breaker.

Trimble said the IRA had "foolishly imposed obligations of confidentiality" on de Chastelain. He urged the IRA to allow the general to reveal more details and thereby "repair the damage that has been done to the process this afternoon."

Trimble emphasized that, unless the IRA offered more detailed commitments to disarm fully and cease to be a threat to Northern Ireland stability, he would not allow his party to revive any administration involving Sinn Fein.

Two brief statements Tuesday from the IRA confirmed the latest disarmament move, but did not offer any of the specific promises sought by other parties to the 1998 deal.

In particular the Ulster Unionists, who agreed in 1999 to form an administration that included Sinn Fein, has insisted that the IRA must stop recruiting and training, gathering intelligence on potential targets, and beating up opponents within its hard-line Catholic power bases.

The IRA was supposed to have scrapped all of its hidden weapons by mid-2000 under terms of the 1998 deal. It began the process in October 2001 but stopped in April 2002 with an estimated 100 tons of weaponry still outstanding.

In a speech Tuesday, Sinn Fein leader Gerry Adams (search) — a reputed IRA commander since the mid-1970s — offered his firmest commitment yet that the IRA would disarm and gradually fade away as a threat to Northern Ireland stability.

"The IRA leadership wants the full and irreversible implementation of the Good Friday agreement in all its aspects and they are determined that their strategies and actions will be consistent with this objective," Adams said.

In its first statement, the IRA said Adams' comment "accurately reflects our position."

Blair had canceled the Assembly election in May because of the IRA's refusal to keep disarming and to promise to halt all hostile activities. Without such commitments, Blair warned that Protestant voters would be likely to reject moderate Ulster Unionist candidates in favor of extremists unwilling to compromise with Sinn Fein.

Trimble angered many Protestants by agreeing in late 1999 to form a 12-member administration that included two Sinn Fein officials.

The crisis-prone coalition collapsed in October 2002 after police accused Sinn Fein's top legislative aide of helping gather intelligence on potential IRA targets. Critics said the outlawed group was keeping open the option of resuming a campaign to abolish Northern Ireland that claimed more than 1,800 lives from 1970 to 1997.