Varadkar tells May: ‘There must be no hard border’

A Number 10 spokesman said the UK continued to look for ‘an innovative way forward’ on the issue. Asked whether Northern Ireland could remain in the customs union following Brexit, the spokesman said: ‘That is a matter for negotiations.’

But a Downing Street source later insisted the Government’s position that the whole of the UK will leave both the customs union and single market after Brexit has not changed.

Irish foreign minister Simon Coveney said it was difficult to see how border checks could be avoided if the UK’s departure from the customs union and single market resulted in ‘regulatory divergence’ between the North and the Republic.

Varadkar has previously suggested a ‘bespoke’ arrangement, similar to that operated on the Isle of Man, under which Northern Ireland, or the whole of the UK, would continue to observe the rules of the single market and customs union without necessarily remaining a member of them.

But Democratic Unionist Party leader Arlene Foster warned against any divergence between the regulatory framework of Northern Ireland and the British mainland, saying: ‘What we don’t want to see is any perception that Northern Ireland is in any way different from the rest of the UK, because that will cause us great difficulties in relation to trade.

‘The single market that really matters to us is the single market of the United Kingdom.’

She accused the Irish government of ‘using the negotiations in Europe to put forward their views on what they believe the island of Ireland should look like in the future’.

Arriving in Brussels for a gathering of leaders from the EU and former Soviet states, May said it was time to move on to the ‘next stage’ in the negotiations, including talks on a free trade deal.

But Coveney insisted EU leaders would not give the green light for the phase two negotiations to begin at their summit in December unless there was progress on the border issue.

He said British assurances on the issue were ‘aspirational’ and that there had to be a ‘credible roadmap’ from the UK setting out how they would ensure there was no return to a hard border.

‘We can’t move to phase two on the basis of aspiration,’ Coveney said. ‘We have move to phase two on the basis of a credible road map or the parameters around which we can design a credible road map to ensure that it doesn’t happen.

‘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.

‘So we need progress on this issue in the context of the regulatory divergence issues.

‘I hope and expect that we can get that by December so that we can all move on.

‘If we can’t, then I think there is going to be a difficulty coming up.’

Coveney added that the other member states were fully behind Ireland’s stance on the issue.