Welcome to your Guardian weekly Brexit briefing, more necessary than ever as it all starts hotting up … If you’d like to receive it as a weekly email, please sign up here. And catch up with our monthly Brexit Means … podcast here.

Finally, producing the Guardian’s independent, in-depth journalism takes time and money. We do it because we believe our perspective matters and it may be yours, too. If you value our Brexit coverage, please become a Guardian supporter. Thank you.

Top stories

And now the hard work really starts. After 17 months of negotiations and a last-minute hitch when Spain threatened to throw a spanner in the works, the EU27 finally signed off on the Brexit withdrawal agreement and political declaration at an extraordinary Brussels summit.

The moment was nothing to celebrate, leaders lined up to say. But for both them and the president of the European commission, only one message mattered: Britain now needed to ratify it. “This is the best deal possible for Britain, the best deal possible for Europe,” Jean-Claude Juncker said. “The only deal possible.”

Theresa May subsequently argued the same to a mutinous Commons. But a majority of MPs disagree – not least the former Brexit secretary Dominic Raab, who two days before the summit helpfully observed that the agreement was worse than staying in the EU since “we’d be bound by the same rules without control or a voice over them”.

Having refused to rule out resigning if parliament votes the deal down – the vote itself has been scheduled for 11 December at the end of a five-day debate – a defiant May said she wanted to “speak directly to the British people” (indeed, she wrote them a letter) and would embark on a campaign to sell the deal to the public.

If parliament failed to back the deal Britain would go “back to square one”, she told MPs, as business leaders rallied to support the deal. Brexiters warned she was storing up trouble over Gibraltar and the French president, Emmanuel Macron, suggested fisheries would be just one of many battles to come during the future trade negotiations.

Things have not, though, got that far yet. For the time being, as the responses from MPs to her Commons statement made abundantly clear, the prime minister does not appear to have the numbers to get her deal through parliament. The hard bit starts now.

What next?

The foreign secretary, Jeremy Hunt, has admitted the government could fall if the agreement is voted down, and Labour is arguing that the government and the EU can be persuaded to prolong the Brexit process by extending article 50 if that is that case.

The DUP, whose leader, Arlene Foster, has said there is no way it can back the deal as it stands, reckons it could consider backing a Norway-style deal as a way to prevent Northern Ireland being treated differently to the rest of the UK.

But what might happen before that? There are at least seven possible scenarios, says the Guardian’s political editor Heather Stewart:

• May could bring it back for a second vote, perhaps with very minor tweaks.

• She could resign and be replaced by a different leader who could then appeal to a majority in parliament, perhaps by offering a softer deal.

• Tory backbenchers could depose her via a no-confidence vote.

• In an ultimate gamble, May could call a general election, appealing to voters to back her over the heads of squabbling MPs.

• Labour could try to force an election through a vote of no confidence.

• Calls for a second referendum could become impossible to ignore, especially if Labour decided to back them.

• Britain could crash out on 29 March without a deal.

Best of the rest

• UK economy would be 4% smaller after 10 years under May’s Brexit plan, the respected economic forecaster NIESR says.

• European court rejects British expats’ referendum challenge.

• Figures show rise in EU nationals exiting public sector after Brexit vote.

• Knighted Tory MP Sir John Hayes says he still won’t back May’s deal.

• Blowtorches in Brussels as protesters demand a people’s vote.

• Britain on verge of historic blunder, Boris Johnson says at DUP conference.

• Philip Hammond insists Theresa May’s Brexit deal is better than staying in EU.

• So will Europe miss the UK when it’s gone? Probably not.

• The leave adviser Shanker Singham admits UK would be better off staying in EU.

• Majestic Wine to stockpile 1m extra bottles for no-deal Brexit.

• The Brexit political declaration – rated.

• The health secretary, Matt Hancock, says second Brexit referendum possible.

Top comment

In the Guardian, Matthew d’Ancona argues that Theresa May’s Brexit deal is already doomed and wonders what happens when MPs reject it:

Even as May shook hands with Jean-Claude Juncker, the political village was transforming itself into a noisy constitutional souk. At every stall, the traders offer alternative models: “Norway for now!”; “Canada ++!”; “Switzerland!”; “Get yer article 50 extension here!” None of these alternatives, it should be emphasised, has been seriously countenanced by the EU. But they are already being offered to curious MPs at early-bird prices. What unites this cacophonous marketplace is the absolute assumption that the deal will fail in December. The 585-page agreement and its 26-page political annex are already regarded as redundant. The variables are dizzying, the stakes vertiginous. The worst news for May is that the past two and a half years were the easy bit.

Top tweet

ITV’s Robert Peston underlines the scale of the task facing the prime minister. Half way through her Commons statement on the summit, he observes: