Former Ulster Unionist leader David Trimble seemed to carry “a resentful complex” towards the Republic of Ireland, a former ambassador said.

Dermot Gallagher also described the late Nobel Peace Prize winner as having “little vision of the kind of leadership that is urgently required at this time in Northern Ireland”, according to newly declassified Irish state papers.

The Irish ambassador to the US made the comments in a letter to an Irish Government official after joining Mr Trimble for drinks in Washington DC in February 1996, two days after the London Docklands bombing.

Mr Trimble was accompanied by Ken Maginnis and Jeffrey Donaldson.

The ambassador wrote that it was Mr Trimble’s view that Gerry Adams “must have known in general terms of the bombing decision, though he probably wasn’t aware of the precise timing and location.

“Trimble also felt that the bombing while not a strictly once-off affair, would not be repeated for some time,” the document outlined.

Mr Gallagher said he emphasised to Mr Trimble the “need for everyone to try and put anger, angst and point-scoring in the past – especially for the leadership on all sides – to now consider urgently how we might salvage the peace process”.

He added: “The alternative was too disastrous to contemplate.”

The ambassador noted that Mr Trimble seemed to welcome the point scoring reference and that he was “clearly irritated during the meeting by Ken Maginnis’ irrelevant ramblings down obscure security boithrins, including his claim that he had known last June that the ceasefire would not last much beyond the new year”.

Mr Trimble made the point “strongly” that any new ceasefire, if it was to be sold to unionists, must carry “credibility”.

“He declined to spell out his thinking on this this other than to hint that some movement by Sinn Fein in the area of consent or in the relation to the Mitchell principles would be helpful. Significantly and helpfully he did not emphasise decommissioning.”

The letter concludes with Mr Gallagher stating that Mr Trimble “while, personally friendly seems to carry a resentful complex towards the Republic and regretfully, to have little vision of the kind of leadership that is urgently required at this time in Northern Ireland”.

He added: “There is an enormous amount of work to be done if we are to develop an effective political relationship with him, the sad point is that those who might help this process are either fairly irrelevant under his leadership (Maginnis) or are, perhaps for career reasons, too tentative to exercise real influence (Donaldson).”

The material can be viewed in the National Archives in file 2022/81/24.