IRISH Foreign Minister Simon Coveney threatened to block Brexit talks from moving on yesterday unless Downing Street addressed Brussels’s threats of a “hard border” with North Ireland.

Speaking at a Brussels summit of EU and former Soviet nations, Mr Coveney insisted that leaders of the bloc’s member states would not give the go-ahead to start phase two of the Brexit negotiations next month without a “credible road map” from Britain.

He again raised the spectre of border posts on on roads between the Irish Republic and Northern Ireland if there was “regulatory divergence” — if the north leaves the EU single market along with Britain.

“The truth is that if we see regulatory divergence between the two jurisdictions on the island of Ireland, it is very hard to see in that scenario how you avoid hard border checks,” Mr Coveney said.

However, Britain and Ireland have been covered by a Common Travel Area agreement — with limited or no border checks — for most of the period since 1923.

The foreign minister claimed he had the backing of the other remaining EU states. “I don’t think Ireland will have to block anything on its own,” he said.

But it was not all plain sailing for Ireland’s government, as coalition partner Fianna Fail vowed to press on with a motion of no confidence in Fine Gail Taoiseach Leo Varadkar’s deputy Frances Fitzgerald.

The row centres on the question of when Ms Fitzgerald learnt of a legal campaign to discredit Garda whistleblower Sergeant Maurice McCabe at an inquiry into his allegations of police misconduct.

Mr Coveney said yesterday that Fianna Fail’s insistence on the question risked causing the five-month-old government to collapse.

“Fianna Fail are behaving recklessly now,” he said. “Ireland does not need an election right now. There is no reason why the Tanaiste should be forced to resign.”