"I can not reconcile the terms of the proposed deal with the promises we made to the country in our manifesto", he said in his resignation letter, published on his Twitter account. We want to keep our journalism open and accessible and be able to keep providing you with news and analyses from the frontlines of Israel, the Middle East and the Jewish World.
The deal covers citizens' rights, Britain's financial settlement and plans for a post-Brexit transition period during which both sides hope to agree a new trade deal.
"The course is clear: we can choose to leave with no deal, we can risk no Brexit at all or we can choose to unite and support the best deal that can be negotiated". Should Brady receive 48 letters from disgruntled Tory MPs, it would trigger a vote of no-confidence against May as party leader, and consequently as prime minister.
An anti-Brexit demonstrator holds a placard opposite the Houses of Parliament in London on Nov 13.
Conservative MP Jacob Rees-Mogg, the chair of the European Research Group comprising party lawmakers who lobby for a hard Brexit or complete break from the EU, declared no confidence in May, and led a series of such letters by MPs.
Raab, whose resignation was the most significant, said: "I can not reconcile the terms of the proposed deal with the promises we made to the country in our manifesto at the last election".
Britain's Brexit Secretary Dominic Raab announced his resignation on Thursday.
Among other Cabinet ministers to resign is Work and Pensions Secretary Esther McVey, who told May the agreement does not "honor the result of the referendum, indeed it does not meet the tests you set from the outset of your premiership".
"It moves the United Kingdom one step away from the nightmare precipice of no deal and the harm it would cause to communities across the country", said Carolyn Fairbairn, head of the Confederation of British Industry (CBI).
Throughout Thursday, the Prime Minister struck a defiant tone, even as four cabinet ministers resigned - including Brexit Secretary Dominic Raab.
Explosive California wildfire wipes out town of Paradise
Cal Fire Director Ken Pimlott said a "very significant, risky weather pattern" would continue through the end of the weekend. Pimlott said six major fires are now burning in California, with three (Camp, Woolsey and Hill) designated "critical".
Thursday's political mayhem prompted a big fall in the value of the pound, which was trading 1.5 per cent lower at $1.2797 as investors fretted that Britain could crash out of the European Union in March without a deal.
"As much as I am sad to see you leave, I will do everything to make this farewell the least painful possible, both for you and for us", said Mr Tusk.
Failure would delay the final settlement until a formal Brussels summit in mid-December, leaving little time for May to get the deal and associated legislation through parliament.
Both members from May's Tory party and opposition Labour told her that her draft deal is disastrous and would not pass the United Kingdom parliament, which is expected to vote on the deal sometime in December.
Instead he argued there should be a second membership referendum, now the terms of a potential exit are known.
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Eurosceptics in May's party have long feared that the prime minister was leading Britain towards a customs union with the EU, something, they say, would mean a Brexit in name.
Sir Keir Starmer said that Labour's opposition to May's plans had hardened in the 24 hours since they were published, and with so many Tories insisting they would rebel, the prime minister had to be forced to consider alternatives. He said Parliament "cannot and will not accept a false choice between this deal and no deal".
"But there's a lot of work that needs to happen to ensure that we have that unhindered supply of medicine". "Stop the clock and go back to Brussels".
"We have been preparing for no-deal and we continue to prepare for no-deal because I recognise that we have a further stage of negotiation with the European Council and then that deal when finalised. has to come back to this House", she told parliament.