The IRA faced fresh pressure to disarm as unionists warned that the Northern Ireland peace process is now coming under huge strain.
As Ulster Unionist leader Mr David Trimble flew to London for talks with the British Prime Minister, his party colleague Sir Reg Empey said republican and nationalist demands risked "wrecking" the political institutions.
The efforts to break the deadlock on decommissioning, demilitarisation and policing are happening against a violent backdrop of sectarian bombings and gun attacks on Catholics across the North.
Although the RUC have yet to make any arrests, officers seized two home-made shotguns and component parts for 10 pipe bombs in Carrickfergus, Co Antrim.
An SDLP group held separate meetings with RUC Chief Constable Sir Ronnie Flanagan and Northern Ireland security minister Mr Adam Ingram to discuss the attacks, which continued overnight in parts of Co Antrim and Co Derry.
Sinn Féin president Mr Gerry Adams warned the Belfast Agreement was doomed unless Mr Tony Blair faced down the "securocrats" within his establishment.
"Unless that change takes place there is little prospect of real progress being made," he said.
"Instead, as an intense and widespread loyalist bombing campaign against catholics intensifies on a daily basis, there is serious risk of deepening crisis and a collapse of confidence in the Agreement."
The latest round of loyalist attacks saw Catholic homes targeted by gunmen and pipe bombers in Larne, Co Antrim, and in Derry.
PA