US officials were concerned about allowing Sinn Féin leader Gerry Adams into the country in 1994 as part of the tentative peace process amid concerns over public sensitivities about terrorism in the wake of the original 1993 World Trade Center bombing in New York.
Mr Adams was allowed into the US, with the Irish government adopting a neutral position to the visa matter. SDLP leader John Hume was strongly in favour of Mr Adams being allowed to travel to New York, but the British government was vehemently opposed.
London was reported to be furious that the matter was even being considered.
Confidential documents released as part of the State Papers revealed how the matter of Mr Adams receiving a US visa became a major issue between the three governments and the Northern Ireland parties in 1994.
US president Bill Clinton intervened to ensure the temporary visa was granted.
US vice-president Al Gore later admitted the administration had “taken a gamble” with the Sinn Féin leader’s visa.
Mr Adams wanted to travel to attend a conference at the Waldorf Astoria Hotel in New York organised in February 1994 by a US non-profit organisation.
All the Northern party leaders were invited in a bid to further the peace process.
One document said US National Security Council member Nancy Soderberg briefed the Irish ambassador in Washington that London was “apoplectic” about the suggestion of the Sinn Féin leader being allowed to travel to the US.
US officials themselves were concerned – not just because of the apparent stance the administration of Mr Clinton would appear to have after the visit.
US officials were concerned that Mr Adams might meet Republican fundraisers and might, as a result, embarrass Washington and its allies.
Ms Soderberg told Irish officials it would be helpful if Mr Adams issued a statement deploring and “renouncing” violence.
She warned Irish diplomats there was “blood on the floor” within the Clinton administration over even the appearance of engaging with Mr Adams, given the recent IRA bombing campaign in Britain.