The European Union has played down talk by Britain's Brexit minister that last week's interim accord is not binding and will launch new talks on Friday (15 December) that are "David Davis-proof", a senior EU official said.
The late-night departure of David Davis has raised the stakes for May, who hailed the hard-won agreement with her deeply divided cabinet of ministers on Friday to keep the closest possible trading ties with the EU.
- Davis, 69, was a surprise appointment to May's cabinet when she took power in 2016, shortly after Britons had voted in favour of leaving the European Union.
Davis quit late Sunday, saying he could not support May's plan to maintain close trade and regulatory ties with the European Union, commonly known as a "soft Brexit", after the departure takes place next year.
"I like Theresa May, I think she's a good prime minister", Davis said.
In a move that unnerved Conservative Party eurosceptics, Steve Baker, a minister who worked for Davis, also quit, saying in his letter to May: "I can not support this policy with the sincerity and resolve which will be necessary". He urged May to abandon her plans and take a tougher line with Brussels.
The plan seeks to keep the United Kingdom and the European Union in a free-trade zone for goods, and commits Britain to maintaining the same rules as the bloc for goods and agricultural products.
It is unclear whether Brussels will accept this, after repeatedly warning Britain it can not "cherry-pick" bits of its single market.
Some Brexiteers dream of replacing May with a staunch Brexiteer, such as Foreign Secretary Boris Johnson, who in the past has disagreed publicly with his boss.
From there, he took a higher degree in business at the London Business School, attending the advanced management programme at elite U.S. university Harvard while pursuing a career on the board of sugar giant Tate and Lyle.
He also served as a reservist in the SAS, the British army's elite special force unit, before entering politics and being elected to parliament in 1987.
Noted for his love of climbing and flying, his ascent in politics began in 1987 when he was elected to parliament, representing a seat in northern England.
He became a government whip ensuring party discipline and later, as Major's Europe minister, delighted in the nickname "Monsieur Non".
Davis then chaired the powerful public accounts committee in the lower House of Commons from 1997 to 2001.
"The Conservative Party doesn't have a great history of changing its leader", he said on LBC radio.
He stayed on as the party's home affairs spokesman, but dramatically resigned his seat to force a by-election in protest at the Labour government's erosion of civil liberties.
If May rides out this crisis - as she has many others - she will face another showdown later this year when she brings the Brexit deal she negotiates with Brussels back to Parliament for approval.
Conservative MP William Wragg, who campaigned for Brexit, said the resignation was "the right thing to do" while Tory MP Andrea Jenkyns, who quit a junior government role earlier this year to "fight for Brexit", said it was "fantastic news", adding: "Well done David Davis for having the principle and guts to resign".