Why is this an important week in the Brexit process?

On Wednesday the 27 heads of state and government will meet on the invitation of Donald Tusk, the European council president, for a second special Brexit summit.

The first, on 25 November, saw agreement between the British government and the EU27 on the 585-page withdrawal agreement and 26-page political declaration sketching out the future relationship.

More than four months have passed, during which the withdrawal agreement has been put to a vote in the House of Commons three times and resoundingly rejected three times. The expected Brexit date of 29 March has come and gone. The next cliff-edge is looming on Friday.

What does the EU want to happen?

As ever with the EU, it is best to go back to the carefully constructed texts known as European council conclusions, the summit communiques agreed by the leaders, to understand where it stands.

On 21 March, at one of its regular summits, albeit one taken hostage by Brexit, the leaders offered an extension of the UK’s membership of the EU to 22 May to allow necessary legislation to pass should the Commons have approved the withdrawal agreement by 29 March. That did not happen.

The EU27 allowed in its 21 March communique for a smaller extension, to 12 April, in the event that the withdrawal agreement failed to be approved. The instruction to the UK was that it would need to “indicate a way forward before this date for consideration by the European council” to avoid leaving the bloc without a negotiated agreement.

One way in which the government could “indicate a way forward” would be to reach an agreement this week with Labour on a vision of the UK’s post-Brexit future, potentially involving a permanent customs union or a Norway-style relationship with the EU. The EU would ideally want to see a positive vote in the Commons on something before the summit. But even if the two leaders merely laid out something in text, May’s suggestion of a short extension to 30 June would have a decent chance of being granted.

European elections would need to be held in the UK on 23 May if the country was still an EU member by that stage.

What if there is no agreement with Labour?

As Jean-Claude Juncker, the European commission president, has said, the EU does not want to kick out a member state. If the Commons held indicative votes and coalesced around a particular vision, it might be good enough for some member states to engage with May’s request for an extension to 30 June. There is, however, very little confidence in the Commons delivering a stable majority for a Brexit deal. That is why Tusk has proposed a “flextension” – a year-long extension to article 50 with the option of leaving the EU earlier once the withdrawal agreement has been ratified.

Is a long extension likely, then?

A number of member states are nervous about the idea. Some fear that the UK could be a difficult partner during its extended membership. Others, including Germany, fear that the flextension idea takes the pressure off MPs to support a deal. France, meanwhile, has been pushing the member states towards a tougher line.

Without a clear and stable majority for something this week, Paris has raised the idea of giving the UK just two weeks or so, to allow the markets to factor in a no-deal Brexit, and then say goodbye.

The thinking is that the British government will very quickly come back to the negotiating table. There should be enough pushback against this idea to prevent it from occurring. But the leaders have offered up surprising conclusions in the past.