Richard Boyd Barrett says any visit will be met with "mass demonstrations"
The Taoiseach Leo Varadkar has confirmed he is to invite US President Donald Trump to visit Ireland.
Mr Varadkar was speaking in Washington DC, where he is to mark St Patrick's Day celebrations.
On Thursday, the his programme includes a bilateral meeting with President Trump at the White House, and engagements on Capitol Hill.
This includes the annual lunch hosted by the Speaker of the House, Paul Ryan.
Taoiseach Leo Varadkar says he’ll invite Donald Trump to Ireland when he meets him tomorrow pic.twitter.com/3l9L3W1Awf— Sean Defoe (@SeanDefoe) March 14, 2018
Mr Varadkar will use these opportunities to emphasise the strength of Irish-US relations, and to highlight the case of the undocumented Irish.
That afternoon, the traditional shamrock ceremony will take place as part of the White House St Patrick’s Day reception.
The Taoiseach will then be guest of honour at a breakfast hosted by US Vice President Mike Pence on March 16th.
Speaking bout the invitation to the president, Mr Varadkar said: "Donald Trump has invited me to Washington DC - I'm here this week.
"He's going to invite me to his house - and I think it's absolutely appropriate - it's just normal hospitality that when someone invites you to their country and their house that you reciprocate".
Political reaction here has been swift.
Labour Party Senator Aodhán Ó Ríordáin condemned the invitation
Senator Ó Ríordáin said: "Taoiseach Leo Varadkar's intended invitation to President Donald Trump to visit Ireland is an insult to the immigrant story of the Irish on the eve of our national holiday.
"President Trump is the most dangerous of modern American presidents, with his hateful anti-immigrant rhetoric dividing America and preying on the most vulnerable of Americans.
"Where Mexican-Americans and Muslim-Americans now walk, the Irish once walked. It is an outrage that the Taoiseach of our country is inviting to Ireland a man who is internationally renowned for the hate that he spawns.
"We are better than that. We are the nation of coffin ships and immigration, of seeking refuge and fleeing violence, of overcoming discrimination and religious intolerance.
"Trump has no place in Ireland. The Taoiseach insults us all by inviting him."
While People Before Profit TD Richard Boyd Barrett said he is appalled by the planned invitation.
He said: "For An Taoiseach to extend an invitation to Donald Trump to visit Ireland is appalling.
"Donald Trump is promoting racist, sexist and warmongering policies that represent a danger to the entire world.
He is literally threating the future of the planet with his decision to withdraw America from the Paris Climate Agreement.
"If Trump does come to Dublin he will be met with mass demonstrations.
"I am certain the majority of people in this country do not like what they hear and what they see from Trump and his brand of obnoxious and dangerous politics are not welcome here."