BELFAST/LONDON/BRUSSELS — The Northern Irish party which props up Prime Minister Theresa May’s minority government demanded on Tuesday that the European Union replace the “toxic” Irish border backstop she agreed, so that the United Kingdom can quit the bloc in an orderly fashion.

With the United Kingdom due to leave the EU in just 52 days, London and Brussels are arguing over whether the deal clinched in November can be changed, raising the possibility of a delay to Brexit, a last-minute deal or a no-deal exit.

Since British lawmakers voted down the withdrawal agreement last month, parliament has instructed May to replace its most contentious element — an insurance policy covering the possible future arrangements for the border in Ireland.

May will try to use a visit to Northern Ireland on Tuesday to reassure communities that she can deliver an orderly Brexit that will ensure peace in a province that was riven by three decades of sectarian conflict until a 1998 accord.

May told her top ministers on Tuesday her objective was to secure legally binding changes to Britain’s EU exit deal to ensure that the country could not be trapped indefinitely in the Northern Irish backstop, her spokesman said.

“The prime minister said that our objective now was to secure a legally binding way of guaranteeing we cannot be trapped indefinitely in the backstop,” the spokesman said following a meeting with May’s Cabinet.

May will use a visit to Brussels on Thursday to update European Commission President Jean-Claude Juncker on discussions taking place in Britain on alternatives to the backstop, an insurance policy to avoid a hard border in Ireland, he said.

“Our position remains clear, and has been expressed several times,” Juncker’s spokesman Margaritis Schinas told reporters at his daily briefing Tuesday.

“A series of votes has taken place in the British parliament, upon the basis of which the prime minister will come to explain what comes next,” he said.

“We will receive her with pleasure,” Schinas said. “While the commission’s position is clear, we are waiting to see what the prime minister has to say.”

The Democratic Unionist Party (DUP), which has propped up May’s government since she lost her parliamentary majority in a 2017 snap election, said it wanted to get a deal agreed but made clear that the border backstop had to be replaced.

“The current backstop, as I have said all along, is toxic to those of us living in Northern Ireland,” DUP leader Arlene Foster, who will meet May in Belfast on Wednesday, told BBC radio.

Foster laced her rhetoric with a call for a solution that would work for all sides and refused to say whether the deal would have to be renegotiated or whether she would accept legally binding assurances.

“If the backstop is dealt with in the withdrawal agreement then, despite the fact we may have misgivings around other parts of the withdrawal agreement, we will support the prime minister because we do want Brexit to happen in an orderly and sustained fashion,” she said.

Britain, Ireland and the EU want to avoid physical checks on the border between Ireland and the British province of Northern Ireland that ceased with the 1998 Good Friday Agreement.

Where British soldiers once manned checkpoints in a reminder of Ireland’s division, the border is currently open and frictionless with no controls as both the United Kingdom and Ireland are part of the EU.

But when the United Kingdom leaves the EU’s Single Market and Customs Union the EU does not want the 310-mile (500 km) border to become a backdoor into the bloc without customs and regulatory checks.

As a way to prevent a hard border, Brussels and London agreed a so-called backstop — basically a promise that unless the sides come up with a better idea then the United Kingdom would remain bound by EU market and customs rules so that goods would not have to be checked.

The backstop is by far the most contentious part of the rejected deal for many lawmakers in Britain. The DUP say it could endanger Northern Ireland’s place in the United Kingdom while Conservative Brexiteers fear being locked into EU rules long-term.

There is little appetite for a no-deal Brexit in the EU and German Chancellor Angela Merkel, the bloc’s most powerful leader, has called for creativity to break the Brexit impasse.

“From a political point of view, there is still time,” Merkel told an economic conference in Tokyo on Tuesday.

“That should be used, used by all sides. But for this it would be very important to know what exactly the British side envisages in terms of its relationship with the EU,” she said. — Agencies