Adams left standing outside White House

The republican leader – who is widely believed to be a former IRA commander but has denied even being in the terror group – said it was “unacceptable” for a security problem to have stopped him from attending US President Barack Obama’s reception ahead of St Patrick’s Day.

In a statement which cast diplomacy to one side, the Louth TD did not attempt to conceal his upset at not being able to attend Tuesday night’s high-powered social gathering.

It was reported by American media that Mr Adams waited for an hour-and-a-half before leaving the White House without getting in.

It is not the first time in recent months that Mr Adams has received a seemingly frosty reception from the Obama administration, and he clearly viewed it as part of a pattern by US officials.

In a statement, Mr Adams said: “When I arrived, the staff at the White House informed me that there was an issue of ‘security’.

“After two decades of travelling back and forth to the USA and countless meetings in the White House with successive US presidents, this is an unacceptable development.

“It is obvious that there remain some within the US administration who seek to treat Sinn Fein differently.

“Some of our political representatives have been denied access to the USA while others, including myself, have to regularly go through additional searches and scrutiny when we travel to and from the USA.

“Last year the State Department initially refused to meet me as part of a transparent effort to pressurise Sinn Fein during negotiations at Stormont.

“That meeting did take place after protests from US political leaders. Efforts to pressurise us in the negotiations failed.”

In a statement which evoked images of black segregation, and sat somewhat incongruously with the first black US president, Mr Adams added: “Sinn Fein will not sit at the back of the bus for anyone. We are elected to represent citizens and we will do this. I am hopeful that the controversy around my White House invitation will help lead to a resolution of all these matters.”

Yesterday afternoon, Mr Adams tweeted an image of his invitation to the White House reception. The invitation began: “The president requests the pleasure of your company...”

Clearly still upset by what had happened, he then tweeted a White House email confirming his attendance and giving details of the acceptable forms of identification to enter the grounds.

But Mr Adams was mocked by some IRA victims.

Austin Stack, whose father was murdered by the IRA, said: “Such a sense of entitlement from a supposed socialist! The victims don’t get to eat canapes at the White House.”

A US State Department spokesman declined to comment on the situation.

Last night Mr Adams was meeting State Department officials in Washington in a meeting arranged prior to the row.