U.K. Prime Minister Theresa May will attack supporters of a second Brexit referendum on Monday as she explains to Parliament why European Union leaders rebuffed her attempt to make her divorce deal more attractive to lawmakers.

May, who accused former Prime Minister Tony Blair of “undermining” her negotiations by pushing for a second vote, will say it would be a catastrophic breach of trust. David Lidington, May’s effective deputy, and Chief-of-Staff Gavin Barwell denied supporting another plebiscite on Sunday after newspaper reports that they’d had talks on the issue.

Another referendum “would do irreparable damage to the integrity of our politics, because it would say to millions who trusted in democracy, that our democracy does not deliver,” May will say, according to extracts of her planned statement to Parliament released by her office. It “would further divide our country at the very moment we should be working to unite it.”

Speculation has intensified about a second referendum on leaving the EU since May withdrew a House of Commons vote on her deal with the bloc last week after it became clear it was headed for defeat. She then survived a bid by her own lawmakers to unseat her as leader of the Conservative Party, and headed to Brussels on Thursday to seek adjustments that would sweeten the deal.

Crash Course

Britain leaves the 28 nation bloc on March 29 and if May can’t find a plan that Parliament will accept, the U.K. will be on course to crash out of the EU without a deal to cushion the blow. British authorities predict the resulting economic damage could include a 25 percent fall in the value of the pound and a 30 percent crash in home prices.

Contingency planning for a “no-deal” Brexit has been stepped up, but May’s office dismissed as “categorically untrue” a report in the Sunday Times that people would be warned not to book holidays after March.

The idea of a second referendum is gaining traction among those who hope it would stop the U.K. leaving the bloc, and those who see it as a threat that will bring Brexiteers behind May’s plan. One Cabinet member said he wants it on the table to convince them that no Brexit at all is a real possibility if they don’t back the prime minister.

Would Threaten Democracy

“It is highly significant that Downing Street felt it had to issue these advance extracts of her statement to the House of Commons,” former Foreign Secretary Margaret Beckett, a member of the opposition Labour Party, said in a statement. “Officials know the prospect of a People’s Vote is being discussed not just in Westminster but in the corridors of Whitehall too.”

Barwell posted on Twitter that “I am not planning a 2nd referendum with political opponents or anyone else” after he was named in a report in the Sunday Times. Lidington tweeted that he has made “plain” his opposition to a repeat vote, and posted an extract from a speech in which he said it would threaten faith in democracy.

Trade Secretary Liam Fox also ruled out a second referendum, but said he would be willing to have lawmakers play a greater role in sifting though alternatives to May’s deal if it’s unable to win enough votes in Parliament.

Limited Options

Some of his cabinet colleagues have been pushing for “indicative votes” to gauge support for different ways forward. They argue that May’s deal will be easier to accept once it is clear there’s no majority for any other option. Fox said it hadn’t been discussed by the full cabinet “yet,” but he “wouldn’t have a huge problem” with backing such a move.

“It wasn’t the government given an instruction in the referendum, it was Parliament, they gave us an instruction and it’s time Parliament carried it out,” he told BBC TV. “When you look at the options that we have, we’ve got to recognize there are a limited number of real-world options here.”

The Labour Party said it will press for May’s deal to face a vote in Parliament before Christmas, and is still considering the best time to submit a no-confidence motion against the government to enhance its chances of winning and taking a step toward forcing a general election.

“We’ve been assessing on a daily basis the time we would achieve a successful outcome,” Rebecca Long-Bailey, the party’s business spokeswoman, told Sky News. “What we want is an outcome rather than it just being a bit of Parliamentary drama.”

Scottish First Minister Nicola Sturgeon, leader of the Scottish National Party, accused Labour, which is divided over what tactics to pursue, of holding up the drive for a second referendum by failing to table a no-confidence motion.

“Labour’s position right now is it won’t back a second EU referendum until it has tried and failed to trigger a general election, but if it won’t try to trigger a general election then we’re in this catch-22 position,” Sturgeon told Sky News. “It seems to me right now that Labour is as much of a barrier to making progress on Brexit as the Tories are.”