Dublin cannot ignore growing support for United Ireland, says Sinn Fein

Party leader Mary Lou McDonald said "poll after poll" had demonstrated the majority of the public would support Irish unity if the UK crashed out of the EU, resulting in the re-emergence of a hard border on the island of Ireland.

"In the event of a hard Brexit, north and south, a majority of people are saying they want a referendum on unity, and the Government need to listen to them," Ms McDonald said.

"At the prospect of a hard border or crash Brexit, it's very clear now in opinion polling that the Irish people have a clear position.

"That comes as no surprise to us at all, but what remains very concerning is that the Government here continues to look away from that reality.

"To start planning for contingency of a border poll and Irish reunification in the event of a crash Brexit, that's the responsible thing to do.

"I don't think it's responsible for Leo Varadkar to have his head buried in the sand, it is time to look dispassionately and in the Irish interest at all contingencies necessary.

"Putting the constitutional question is now an obvious matter that the Government needs to consider and plan for."

In Westminster, amid a revolt among backbenchers and her DUP allies, Prime Minister Theresa May has swung behind a motion amendment that would allow her to go back to Brussels and seek changes to the Irish border backstop.

Ms McDonald reiterated that the Irish Government should remain steadfast in its commitment to the backstop.

"The Taoiseach needs to remain absolutely firm," Ms McDonald said. "There cannot be any renegotiation of the backstop."

The Taoiseach has previously said that raising the prospect of a border poll is "disruptive and destructive" to getting a Brexit deal ratified.

Deputy leader Simon Coveney previously said the issue could "create an even more divisive debate and atmosphere in Northern Ireland, which is the last thing we need".

A poll conducted by RTE'S Claire Byrne Live on Monday night showed 86% in the Republic would opt for a united Ireland over a hard border.