Sinn Fein is to seek a meeting with the US Ambassador Kevin O’Malley over the treatment of some of its TDs in the United States.

Party leader Gerry Adams was denied entry to a White House reception despite having an invitation, over a security issue. 

Sometimes it's harder 2 get outta the USA than it is 2 get in2 The White House. Dreaded SSSSs. pic.twitter.com/XjxG5kCy4Z

— Gerry Adams (@GerryAdamsSF) March 18, 2016

Deputy leader Mary Lou McDonald also this morning confirmed she had been subject to what she called 'invasive' security screening.

Ms McDonald accused "stringent security" of singling out individuals on the basis of their political views.

"The administration in the United States is well aware that Sinn Fein and the leadership of Sinn Fein over many years have been architects of the peace process, [and] are a force for good," she said.

“We are not looking for special treatment but I would ask for myself as to why I would merit special security checks, why any member of Sinn Féin merit special security checks,” the Dublin central TD added.

After being refused entry to the White House due to what was later revealed to have been a clerical error, Gerry Adams called for "the full normalisation of relations between Sinn Féin and the White House, and a review of the US security arrangements for Sinn Féin representatives visiting the country."

While he excepted the White House's apology, Mr Adams has written to US authorities seeking additional information regarding the security issue that resulted in the Sinn Fein leader not being let into the St Patrick's Day event.