Leo Varadkar is accused by Democratic Unionists of trying to ‘decouple’ Northern Ireland from rest of UK in Brexit settlement

Two of the 10 Democratic Unionist MPs whose votes keep Theresa May in power have accused the Irish prime minister, Leo Varadkar, of ramping up tensions on the island over his stance on Brexit.

Varadkar’s insistence that Northern Ireland could stay in the single market and the customs union was “unhelpful and obstructive” in terms of the Brexit negotiations, Sir Jeffrey Donaldson told the Guardian.

The DUP leader at Westminster, Nigel Dodds, said Varadkar was “upping the ante” and alienating the unionist community over allegedly trying to “decouple” Northern Ireland from the rest of the UK in terms of a Brexit settlement.

Dodds, the MP for Belfast North, said: “You have Leo Varadkar’s minister Simon Coveney standing up in the Dáil last week talking about achieving a united Ireland in his lifetime. You have Leo himself warning that either Britain stays in the customs union and the single market, and if not then Northern Ireland should do so alone.

Q&A Why is Dublin opposed to the idea of a hard border? Show Hide Ireland’s taoiseach, Leo Varadkar, has been much more sceptical than the UK about the potential for avoiding border posts via virtual checks on importers. Whilst agreeing with British ministers and EU negotiators that it is inconceivable for there to be a return to a hard border with the north, Dublin argues that the best way for the UK to achieve this would be by permanently remaining in a customs union with the EU and seeking single market membership like Norway through the European Economic Area. The UK has conceded that some of this will be necessary in its interim phase after Brexit, but hopes clever technological solutions can allow it have looser economic links in the long run. Varadkar is not alone in being sceptical about whether such a cake-and-eat-it customs and trade strategy is viable.

“This is about decoupling Northern Ireland from the rest of the UK economy and it won’t work. All it is doing is increasing tensions, which is unfortunate because up to now we have had a very good relationship with the Irish government.”

Dodds added: “He [Varadkar] should get a grip and get real. With all this talk of customs unions and single markets he is in danger of not working on the practical issues with the UK to sort out the border and trade. By going down this road ultimately he is in danger of acting against the republic’s own self-interests [which] rely so much in terms of trade and exports with the UK.”

Ahead of the DUP’s annual conference in Belfast on Saturday, both Dodds and Donaldson predicted that their party’s support for the minority Conservative government would last its full five-year term.

Donaldson said it was “wishful thinking” on the part of Labour to claim the DUP deal to prop up the Tories would fall apart next year.

On the stance of the fragile Irish government ahead of the Brexit summit in Brussels on 14 December, Donaldson claimed Varadkar’s government was being dictated to by Sinn Féin on the European question.

Facebook Twitter Pinterest Sir Jeffrey Donaldson: ‘The Irish government is being very unhelpful.’ Photograph: Brian Lawless/PA

“The Irish government is being very unhelpful in the way they are trying to insist that Northern Ireland remains in the customs union and the single market. What Leo Varadkar has to realise is that the UK is leaving both and that includes the whole of the UK including Northern Ireland,” Donaldson said.

“He is also in danger of a self-fulfilling prophecy about a hard border because while he makes unrealistic demands over the single market and the customs union we are all missing out on hammering out the practical things that can be done to prevent a hard border. Time is running out to do that if he continues to fixate on the single market and the customs union.”

Donaldson said the DUP was opposed to the reimposition of a hard border on the island.

The goodwill Varadkar had generated among the unionist community in the run-up to Remembrance Sunday, when the Irish taoiseach wore a poppy during a Dáil debate, had been lost over his stance towards Northern Ireland and Brexit, Donaldson added.

On the future of the DUP deal that ensures May remains as prime minister, he said: “We need a government that will deliver a good Brexit, which would take up to four years. So by then this government will have served out almost its entire term of office. Conversely, we don’t believe for one moment that Jeremy Corbyn could deliver any kind of Brexit let one a good one for the British people.”

But he said it was irrelevant if the Tories ever chose to replace May as leader.

“The DUP did a deal with the Conservative party, not with any individual,” he said.

The DUP has 10 MPs in the Commons whose votes are crucial in keeping the minority Conservative government in power.

Seven of the eight remaining Northern Ireland Westminster seats are held by Sinn Féin, which boycotts the Commons.