The SDLP has announced it will boycott any White House function under a Donald Trump presidency.
The leader of the nationalist party, Colum Eastwood, called on other Irish and Irish American politicians to snub the Republican candidate if he is elected to the Oval Office.
Political leaders from both sides of the Irish border are usually on the guest lists of St Patrick’s Day events in Washington every March.
Mr Eastwood branded Mr Trump’s controversial comments on women, immigrants and minority communities as “absolutely grotesque”.
“Donald Trump has proven over the course of a 16-month campaign that he is not just a populist or a fool but a bigot,” he said.
“This man has plumbed the depths of dehumanising and dangerous rhetoric aimed at stirring up sectarian, racial and xenophobic hatred.”
He added: “As Leader of the SDLP and the progressive nationalist tradition on this island, I will not give any support to such an administration, founded on bigotry, by attending the White House under a Trump presidency.
“It is incumbent on other Irish and Irish American politicians to make similar declarations.
“The people of Ireland know, better than most, how dangerous the politics of hate and division can be.
“We have suffered at the hands of those who seek to divide people on the basis of their faith or their nationality.
“It is our duty, given the unshakable bond between our people and the people of the United States, to take a stand against those who seek to perpetuate similar division.”