CNN  — 

UK Prime Minister Theresa May has announced yet another attempt to get her serially rejected Brexit plan through Parliament – and this time she dangled the prospect of a second referendum to get it across the line.

May used a speech in London to outline what she claimed was a “new Brexit deal,” which in reality looked a lot like her old Brexit deal with some added sweeteners designed to attract the support of dubious Members of Parliament.

“If MPs vote against … this bill, they are voting to stop Brexit,” May said.

In an attempt to repackage the plan, which has already been rejected three times by the House of Commons, May rolled it up into a wider set of legislation dealing with Britain’s departure from the European Union. As well as the offer of a second referendum, it also contained pledges on workers’ rights, environmental provisions, as well as a temporary customs relationship with the European Union.

Failure to agree the deal would lead to a “nightmare future of permanently polarized politics,” she said.

But the central provisions of the deal remain the same, and May had barely finished speaking before her plan ran into significant opposition. “The Prime Minister’s proposals are worse than before and would leave us bound deeply into the EU,” said Jacob-Rees Mogg, a Conservative MP and leader of a pro-Brexit bloc in the Prime Minister’s party.

Supporters of a second referendum – a so-called “people’s vote” – were unconvinced the process laid out by May. Margaret Beckett, a Labour MP who backs the official people’s vote campaign, described it as a “hotchpotch offer” that should be rejected.

When May puts her Withdrawal Agreement Bill before the House of Commons in the first week of June, it will mark her fourth attempt at getting it passed. It is likely to be May’s last, as she faces increasing pressure to quit.

The vote will coincide with US President Donald Trump’s forthcoming state visit to the UK. It will also take place in the aftermath of what is likely to be a disastrous performance by the Conservative Party at the European elections, participation in which May had hoped to avoid.

And it comes after the failure of cross-party talks designed to break the impasse. May said she recognized that opposition MPs would need to support her deal if it were to stand a chance of passing. “I say with conviction to every MP of every party – I have compromised. Now I ask you to compromise too.”

The 10-point plan that May laid out Tuesday places a legal obligation on the government to seek alternative arrangements to the controversial “backstop” arrangement, an insurance policy designed to avoid a hard border on the island of Ireland, by December 2020. The backstop is opposed by the Democratic Unionist Party (DUP), whose 10 MPs prop up May’s minority government in Parliament.

The DUP was not convinced by the guarantees. “We will examine the legislation closely when the bill is finally published but the fundamental flaws of the draft Withdrawal Agreement treaty itself remain unchanged,” said the DUP’s parliamentary leader, Nigel Dodds.

Given the failure to win over the DUP, Conservative Brexiteers and Labour moderates, May’s “new” deal appeared on Tuesday to be heading the way of her previous ones – dead on arrival.

Correction: This story has been updated to correct the name of Margaret Beckett, the Labour MP who supports a second referendum.