The Democratic Unionist Party (DUP) has written to the United States Vice President Joe Biden seeking an apology following a joke the Vice President made on St. Patrick’s Day when greeting Ireland’s Prime Minister Enda Kenny.

Biden said, “Anyone wearing orange is not welcome in here” and added that he was “only joking.”

The comment was made as he welcomed Kenny and his wife Fionnuala to the Naval Observatory on Tuesday in Washington, DC. for the annual Vice President's St. Patrick’s Day breakfast.

The South Antrim Member of Parliament and Justice Spokesman for the DUP Reverend William McCrea wrote to Biden seeking an apology.

He told the Irish Times, “Whether they were intended as a joke or not, the comments are a slur on those who would be known as ‘orange’ ie Protestants.

“This term is much wider than anyone who is a member of the Orange Order. It has traditionally been used to define people from the Protestant faith.”

McCrea called for Biden to apologize for his remarks and “take corrective action” to ensure that Protestants were welcome at his home.

He added, “Undoubtedly if he had made such a remark about any other faith group there would be calls for his resignation.”

The spokesman said that Northern Ireland had made an effort to make sure that St. Patrick’s Day was “inclusive” and said Biden’s comments were “disgraceful and careless.”

Observers said the timing of the comments was unfortunate due to that fact that negotiations in Northern Ireland over welfare reform are currently at an impasse. Sinn Fein shocked those involved last week when it withdrew support for welfare reform measures. Both Martin McGuinness and Peter Robinson canceled their planned trips to the United States for St. Patrick’s Day in order to deal with the situation.

Biden and Kenny discussed the situation during the Taoiseach's visit.

Later on St. Patrick’s Day Biden said "genius" is required to ensure the Stormont House Agreement is maintained.

He called on Northern Ireland leaders to build “unity and trust" to ensure the agreement is "locked down."

Biden said, “I still think the Stormont House Agreement will hold. That’s my hope.

“We need genius on all sides to lock this agreement down.”

He added that “unity and trust” would be needed to make the agreement work.

“And finally, finally, finally bring an end to this dark chapter. We are anxious for that to happen,” said Biden.

Taoiseach and Fine Gael leader Enda Kenny with his wife Fionnuala O Kelly and Vice President Joe Biden before breakfast at his residence in Washington USA.Photocall / Merrion Street