Brexit deal - as it happened: Theresa May's late-night scramble to seal a deal as EU finally gives green light for future trade talks

An interesting detail in the joint agreement shows that people in Northern Ireland will retain their EU citizenship after Brexit.

The text reads:

Both Parties acknowledge that the 1998 Agreement recognises the birth right of all the people of Northern Ireland to choose to be Irish or British or both and be accepted as such.

The people of Northern Ireland who are Irish citizens will continue to enjoy rights as EU citizens, including where they reside in Northern Ireland.

Foreign Secretary Boris Johnson - one of the Cabinet's most ardent Brexiteers - has tweeted his congratulations to the Prime Minister.

More detail on the talks behind the scenes, where the DUP warned Theresa May against today's deal because of levels of opposition on the Conservative benches.

Former Ukip donor Arron Banks, who founded the Leave.EU campaign, has issued a stinging rebuke to the PM, accusing her of "betraying the country and the 17.4m Leave voters".

Reporters in Brussels are tweeting that Britain's divorce bill will be £35bn to £39bn - which is less than originally estimated.

Now that the European Commission has agreed that "sufficient progress" has been made, what happens next?

Press Association Political Editor Andy Woodcock has compiled a helpful timeline, looking ahead to the next stage of the Brexit process.

2017

:: December 13 - European Parliament debates and votes on the joint report drawn up by negotiators for the UK and EU on the divorce issues of citizens' rights, the Irish border and the financial settlement.

:: December 14-15 - Leaders of the remaining 27 EU states, meeting at a scheduled European Council summit, are expected to give the green light to move negotiations on to trade and the transition to a post-Brexit relationship.

:: December 20 - The EU (Withdrawal) Bill is due to complete the crucial committee stage in the House of Commons, with further debates in both Houses of Parliament expected to take up months of 2018.

2018

:: Winter/spring - Negotiations on the transition to future EU/UK relations, along with "exploratory talks" on a possible free trade agreement.

:: March 22-23 - European Council summit in Brussels. An opportunity to assess what kind of trade deal can be expected.

:: May - English local government elections will provide the Prime Minister Theresa May with her first widespread electoral test since the disastrous snap election of June 8 2017.

:: October - A final agreement on withdrawal and transition should be ready by this point in order to allow time for ratification before the end of the two-year Article 50 deadline. A free trade deal could take longer to finalise, and many observers believe it may not be in place until long after the date of Brexit.

2019

:: Winter/spring - Possible ratification process involving up to 38 national and regional parliaments, with any of them effectively holding a veto.

Brexit Secretary David Davis has promised that Parliament will have to approve any deal in a Withdrawal Agreement and Implementation Bill, although this will be on a "take it or leave it" basis. MPs will consider the legislation before MEPs in the European Parliament carry out the final vote on any agreement.

:: March 29 - Two years after the invocation of Article 50, the UK ceases to be a member of the EU and is no longer subject to its treaties, whether or not a withdrawal agreement has been reached. Because the exact moment of exit is midnight Brussels time, the UK is due to leave at 11pm on March 29. Under the terms of the EU (Withdrawal) Bill, the bulk of Brussels legislation would be automatically transposed on to the UK statute book.

Plans for people in Northern Ireland to keep EU citizenship after Brexit has prompted some anger, with Labour MP Steve Reed demanding the same rights be extended to people in his Croydon North constituency.

But if you look closely at the detail (see here) - it applies to Irish citizens living in Northern Ireland.

Europe correspondent Jon Stone explains the maths behind the £35bn - £39bn divorce bill figure, which was originally put at £50bn.

He sends this report:

There isn’t an official figure for the divorce bill in the joint text agreed last night, but British officials close to the discussions say that if you follow through the methodology to calculate the number you get between £35 billion and £39 billion.

This is worked out by noting that Britain will pay somewhere between €17 billion and €18 billion into the 2019 ‘multi annual financial framework’ (MFF) – effectively the EU's budget round. 

It will also pay between €21 and €23 billion into the so-called “RAL” – effectively a credit facility for the EU whose acronym come from the French term “reste à liquider”.

Officials would also add to this between €2 to €4 billion for actual liabilities Britain owes the EU – mostly things like the future pensions of European civil servants.

But the EU also owes Britain money. The final figure quoted by officials subtracts money owed back to the UK from its share of the European Investment Bank’s capital, which is around €40 and €45 billion.

Total all that up and convert it into pounds, and at current exchange rates Britain will be paying net £35 billion to £39 billion. This will all be paid over a period of time, as if Britain was still in the EU, rather than in one big lump.

Scottish Tory leader Ruth Davidson has sent out a statement, describing the news as "a real step forward".

She said: "Throughout this process, my overriding priority has been to ensure we act as one United Kingdom and no home nation is left behind. I am therefore glad that this morning's agreement ensures the integrity of the UK.

"The work on a comprehensive trade agreement with the EU27 can now begin.

"This will require more hard work and patience. But I am optimistic that Britain and Europe can together build a new relationship, underpinned by the ties of trade, shared values and mutual interest. It is in all our interests."

She also fired off criticism at SNP rival, Scottish First Minister Nicola Sturgeon on Twitter: