Here are the whats, whys & wherefores

What has been agreed?

The Brexit deal was agreed by EU leaders in 38 minutes yesterday at a special summit in Brussels.

There are two parts to the package: the withdrawal agreement which sets out the terms of the divorce and the political declaration, which is the route map for the UK and EU’s future trade and security relationship.

This deal now has to be agreed by the UK Parliament and the European Parliament before we leave on March 29 next year.

What happens next?

Theresa May has a frantic two weeks in which to sell her deal to MPs and the public. The Commons is expected to vote on the withdrawal agreement during the week beginning Monday, December 10.

The PM says this is the only deal on offer and it is a choice between her plans, no deal or no Brexit at all.

Why is the deal so unpopular?

Conservative Leave MPs say the withdrawal agreement leaves us bound by EU rules and regulations with no say over them. Many Tory Remain MPs, such as Jo Johnson, share this concern.

Brexiteers are most exercised by the Irish backstop which promises no hard border between Northern Ireland and Irish Republic. This says that, if no other solution can be found, then Northern Ireland will remain within the orbit of the EU.

The DUP says the Irish backstop would result in a border down the Irish Sea – effectively splitting Northern Ireland from the rest of the UK – and are also refusing to back the deal.

What does Labour say?

Jeremy Corbyn says the agreement fails to meet its six tests. These are a deal that provides the exact same benefits of the single market and the customs union, a strong and collaborative relationship with the EU, protects workers’ rights and environmental standards, a fair system of migration, protects national security and delivers for the nations and regions of the EU.

While Mrs May’s deal fulfils some of these demands it does not give access to the single market and the customs union, while the section on workers’ rights is time-limited. Labour says it would renegotiate a better outcome. The question is if the EU, which says May’s deal is the only one on the table, would be willing.

Can Mrs May get it through Parliament?

At the moment it is hard to see where the numbers are. The vast majority of the Labour Party, the SNP and the Lib Dems will vote against as well the 10 DUP MPs. So far as many as 80 Tory MPs have said they will vote against the Government.

Downing Street is now in a race against time to get as many MPs as possible to change their mind.

Mrs May is trying to appeal over Parliament’s head by appealing to the public that her deal is in the national interest in the hope voters will put pressure on their MPs. But if this tactic fails she could be forced to look at rewriting the withdrawal agreement or adding some last-minute caveats.

What happens if the Commons votes against the deal?

We are in uncharted territory. The PM, if she survives, could submit the agreement to a second vote of MPs.

Another option is the Commons votes to send Mrs May back to the negotiating table. But, with time running out, this would require extending Article 50, which in turn needs the approval of all 27 EU states.

There could be another general election but Tories will not want to risk any move that could allow Jeremy Corbyn into No 10. Another possibility is MPs decide to send the issue back to the people by holding a second referendum. Or we crash out without a deal.

Read more analysis at mirror.co.uk:/authors/jason-beattie/