The new-found relationship between London and Dublin through the workings of the Anglo-Irish Agreement was regarded by the British as “a nuisance”, apart from the security aspect.

This was the view of a senior Northern Ireland Office official in 1988, according to previously confidential files released on Thursday in Belfast.

In a briefing document for Sir John Blelloch, the incoming head of the NIO, in the wake of the rejection of the 'Birmingham Six' appeal and the decision not to prosecute RUC officers named in the Stalker-Sampson 'shoot to kill' inquiry, Peter Bell described Anglo-Irish relations as "perhaps under greater strain than at any time since the Agreement was signed".

The official acknowledged “the damage done to confidence in our policies in Dublin, the US and to our image in the world generally”.

Bell expressed the hope that the British side would grasp “the damage to our interests as Irish sensitivities are severely bruised ... But ultimately serious misunderstandings will continue to occur unless [British]Ministers collectively see the Anglo-Irish relationship more positively than as a vehicle for enhancing cross-border security operation. But otherwise, it sometimes seems, as a bit of a nuisance.”

In his view, Anglo-Irish relations should be treated as a “non-zero sum-game”.

In particular, the official noted the continual rejection by the NIO of the Irish Government's nominations to NI bodies: "The Irish are already dismayed that we shall be rejecting their candidate for the new Police Complaints Commission. [this] is only the latest in a series."

The Irish candidate, he noted, a local Catholic solicitor, Christopher Napier "was not thought suitable owing to his activities in the early 1970s".

The late Chris 'Kit' Napier, a brother of the former Alliance Party leader, Sir Oliver Napier, was a leading Irish language enthusiast and subsequently became Taxing Master in Northern Ireland.