(Bloomberg) -- Northern Ireland’s Arlene Foster, whose Democratic Unionist Party is propping up Theresa May’s government, thinks Britain’s probably going to crash out of the European Union next year without a deal, the Observer reported in its Sunday edition.

The newspaper obtained what it called an “explosive set of emails” in which Foster reportedly told a Conservative lawmaker in Brussels that her party was preparing for a no-deal Brexit. An agreement is the least likely outcome because of the EU’s stance regarding Northern Ireland, she was reported saying. It was a recent meeting Foster had with EU chief negotiator Michel Barnier that prompted her view.

Officials are trying to hammer out a deal this weekend for a public announcement on Monday and a leaders’ summit on Wednesday. People familiar with both sides of the negotiation told Bloomberg earlier that the biggest obstacle was to avoid a border emerging on the island of Ireland without erecting one between Northern Ireland and Britain. Sterling has strengthened against the euro since reaching a trough in late August, partly on bets that the recent political rhetoric suggests some sort of agreement is more likely than not. Foster’s reported comments suggest that optimism may be misplaced.

Foster, who’s scheduled to meet Irish Prime Minister Leo Varadkar on Monday, has said she’d reject any deal in which Northern Ireland was treated any different from the rest of the U.K. At the same time, right-wing hardliners in May’s party have balked at any backstop arrangement that could lock the country for longer into accepting EU regulations without having any say in their makeup.

Call for Mutiny

Former Brexit Minister David Davis, writing in the Sunday Times, urged senior ministers to rebel against May’s “flawed” plan to keep the nation in the customs union with the EU.

“This is one of the most fundamental decisions that government has taken inmodern times. It is time for the cabinet to exert their collective authority,” he wrote. “This week the authority of our constitution is on the line.”

Meanwhile, the Telegraph reported that 63 Tory lawmakers, include Davis and Jacob Rees-Mogg, signed an open letter attacking the government’s behavior before the backstop decision. The group’s concerned that voters will rebel at the ballot box -- it thinks there could be few of the mooted benefits of quitting the EU by the time of the next election in 2022.

The government needs to publish cross-Whitehall Brexit analysis so that experts from all sides can study it, the letter stated: ‘It is unacceptable that the Government leaks the results of its modeling when it suits but simultaneously hides what lies behind these forecasts from the public.”

In another twist to the British weekend rumor-mill, the Independent reported that several Labour Party lawmakers are prepared to support May in a U.K. parliamentary vote if the alternative is a no-deal vote. At least 15 could back the government, which could be enough to get the measure through the House of Commons.

--With assistance from Maria Jose Valero.

To contact the reporter on this story: James Ludden in London at jludden@bloomberg.net

To contact the editors responsible for this story: Matthew G. Miller at mmiller144@bloomberg.net, James Ludden, Ros Krasny

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