The Sinn Fein leader has been condemned for marching behind an “offensive” banner in New York’s St Patrick’s Day parade.
Mary Lou McDonald helped carry a sign which read “England Get Out of Ireland”, as she took part in the city’s annual parade to mark the Irish national day on Saturday.
Ireland’s Foreign Affairs Minister Simon Coveney accused Ms McDonald of poor leadership and of being an embarrassment over her actions.
He tweeted: “@MaryLouMcDonald this is NOT leadership – it’s offensive, divisive and an embarrassment – grow up, this is NOT #Ireland in 2019! we are better than this!”
Mr Coveney made the remarks after Sinn Fein posted a photograph of their party leader at the parade.
The tweet read: “No explanation needed. @MaryLouMcDonald #StPatrickDay Parade #NYC.”
Ms McDonald was in the United States to take part in the annual St Patrick’s festivities.
In an earlier post, the Tanaiste commended New Zealand prime minister Jacinda Ardern in the wake of the mass shootings in Christchurch.
He wrote: “This is what Leadership looks like – @jacindaardern #NewZealandTerrorAttack”.
His tweet was accompanied by a video of Ms Ardern wearing a hijab as she met the families of the victims of the mosque shootings.
Ulster Unionist Party leader Robin Swann also condemned Ms McDonald’s actions.
Mr Swann said: “Once again Mary Lou McDonald as president of Sinn Fein, has shown them up for what they are really all about as she posed behind a banner which was highly offensive and wrong on so many levels.
“It demonstrated that bigotry and hypocrisy were alive and well within their version of republicanism.
“It is clear that when Sinn Fein talk about respect, honesty and integrity, that they are as sincere as Gerry Adams using equality as a Trojan Horse to attack unionists. Their words about rights are only a veneer to hide their true intention.”
He added: “It is sad that whilst others celebrate St Patrick in a respectful and non-confrontational manner, Sinn Fein return to type.”
Democratic Unionist Party’s Gregory Campbell said Sinn Fein’s caption on the tweeted picture, which read “No explanation needed”, summed up the party’s attitude to explanations, truth and respect.
“When slogans such as “Brits out” or “England out of Ireland” are used the unionist community are well within their rights to see themselves as the intended focus,” Mr Campbell said.
“The ‘British presence in Ireland’ is the unionist population in Northern Ireland.
“The Republican focus on “Brits” in the city of Londonderry saw thousands of unionists move out en masse from the Cityside as the IRA began their ‘war’.
“It’s clear that republicans don’t do explanations. Neither do they do apologies. They’ve never explained let alone apologised for the terror their armed wing conducted for so long.”
In response to the criticism a Sinn Fein spokesman said: “The most divisive and offensive act on this island for almost the last 100 years has been the partition of Ireland.
“It should come as no surprise that Sinn Fein wants a new united Ireland under the provisions of the Good Friday Agreement.
“The faux outrage of some of our political opponents owes more to the silly season of a holiday weekend and petty political point scoring.
“However if Simon Coveney and the Government is serious about achieving a new and agreed united Ireland then he should immediately convene an all-Ireland forum on Irish unity.”