The leader of the loyalist political party linked to the Ulster Volunteer Force tonight had "no doubt" a bomb factory found in north Belfast was linked to his associate organisation.
But Assembly member David Ervine of the Progressive Unionist Party insisted the UVF was not involved in the recent spate of more than 50 attacks on Catholic families across Northern Ireland which had been blamed on the rival Ulster Defence Association.
The haul - which included 11 pipe bombs, home-made explosives and a substantial primed and ready bomb consisting of 45lbs of explosives packed into a fire extinguisher - was discovered in a flat in a block in the Mount Vernon area which is more known as UVF territory than that of the UDA.
Meanwhile dissident republicans were again shown to be active.
Gardaí discovered a "barrack buster" mortar bomb in remote woodland close to the border in Co Donegal.
Against the back-drop of terrorist activity, talks between British and Irish officials and Sinn Féin continued as efforts intensified to resolve the decommissioning, demilitarisation and policing disputes threatening the entire Ulster political process.
Sinn Féin's Martin McGuinness said: "We made limited progress last week. We want to make more progress this week."
In north Belfast, police officially said it was too soon to say more than that the bomb factory was "undoubtedly loyalist" and its discovery had "undoubtedly saved lives".
But senior security sources joined Mr Ervine in pointing the finger at the UVF.
Mr Ervine said: "I have no doubt that it was their material - the question being asked is ‘what for'.
"What I can say - especially against the hype and backdrop that has been created with this spate of sectarian pipe bombings - I am assured and I am certain that that style has not been used, and there was not the intention to use them for that purpose."
Mr Ervine said the bomb factory may have been there for some time and pointed to the feud between the UDA and UVF which started last summer and was resolved last month as a possible reason for it.
He said a investigation within the organisation was under way and when he was given the answer "the people of Northern Ireland will hear it loud and clear".
Mr Ervine was clearly concerned that 1,000 ecstasy tablets and a quantity of cannabis found in a neighbouring flat during the same security operation was linked to the UVF.
He said he and his party fellow assembly member Billy Hutchinson would have to consider their positions as political representatives of the loyalist terror group if there was a link between the two.
"My colleague and myself would have some grave, grave difficulties and would undoubtedly have to review our position."
PA