TOPSHOT - Britain's Prime Minister Theresa May arrives at the European Council in Brussels on October 17, 2018. - British Prime Minister Theresa May is due to address a summit of European Union leaders in which Brexit negotiations are expected to be top of the agenda. (Photo by EMMANUEL DUNAND / AFP)        (Photo credit should read EMMANUEL DUNAND/AFP/Getty Images)
The future of Brexit remains uncertain
02:42 - Source: CNN
London CNN  — 

Britain could be trapped in endless negotiations with the European Union by Theresa May’s Brexit deal, the British government’s top legal adviser has warned.

In the full written advice by the attorney general, which the government was forced to publish after lawmakers found it in contempt of parliament, ministers are warned that the “backstop” insurance policy relating to Northern Ireland could last “indefinitely” if relations with the EU break down.

The six-page document, dated November 13, was described as “devastating” by the Democratic Unionist Party (DUP), the small Northern Ireland party that has been propping up the UK Prime Minister in parliament.

In the advice, Attorney General Geoffrey Cox warns that the Northern Ireland “backstop” could last “indefinitely until a superseding agreement took its place.” The UK could become involved in “protracted and repeating rounds of negotiations,” he warns.

He advises that the so-called backstop would “endure even when negotiations have clearly broken down.”

The backstop is an arrangement designed to ensure there is no return to a “hard border” between Ireland, which will remain part of the European Union after Brexit, and Northern Ireland when the United Kingdom leaves the bloc next March.

Lawmakers are debating the government’s Brexit plan for a second day Wednesday, ahead of a vote on the deal next week.

Labour: Advice reveals ‘central weaknesses’ in plan

Shadow Brexit Secretary Keir Starmer, of the opposition Labour Party, tweeted: “Having reviewed the Attorney General’s legal advice, it’s obvious why this needed to be placed in the public domain.

“All week we have heard from Government ministers that releasing this information could harm the national interest. Nothing of the sort. All this advice reveals is the central weaknesses in the Government’s deal.”

Starmer said it was “unthinkable” that the government had tried to keep the advice from Parliament and the public before MPs vote Tuesday on the Brexit deal.

DUP deputy leader Nigel Dodds said it was clear from the attorney general’s advice “that we were right to advocate its full publication and we have been vindicated in our opposition to the backstop arrangements contained within the withdrawal agreement.”

He said the truth was “now laid bare for all to see in that the backstop will not be temporary in nature” and that it risked creating a situation where Northern Ireland remained in the EU customs territory while the rest of the UK did not.

“The legal advice makes clear that the current drafting of the backstop does not provide for a mechanism that is likely to enable the UK lawfully to exit,” he said in a statement.

“This advice concisely sets out the stark reality of the operation of the backstop. Its publication demonstrates how the Prime Minister has failed to abide by the commitments she gave in that the United Kingdom as a whole would leave the European Union and that she would ensure there would be no customs or regulatory divergence within the United Kingdom.”

Three defeats

On Tuesday, May suffered the worst day in Parliament for a British government in 40 years, losing three crucial votes related to Brexit.

The unprecedented contempt vote was prompted by the government’s refusal to publish the full legal advice, despite having previously accepted a parliamentary motion directing it to do so.

Cox had argued it was not in Britain’s national interest to publish it in full, and instead offered a summary to Parliament on Monday. “There is nothing to see here,” Cox insisted. May told her Cabinet on Tuesday that “candid” legal advice given to ministers must remain confidential.

Starmer told the House of Commons that the government was “willfully refusing to comply” with the binding order issued by lawmakers. “That is contempt,” he said, adding that the government had ignored the motion for months.

CNN’s Kieron Mirchandani and Lindsay Isaac contributed to this report.