Britain is due to remain an EU member until 31 October after agreeing a six-month extension

What are the key dates between now and the new Brexit deadline?

This week, a six-hour debate among EU leaders concluded with Theresa May being offered a six-month extension to article 50.

Britain will remain a member state of the EU until 31 October, with the option to leave earlier if the prime minister can secure House of Commons support for her Brexit deal.

Here are some of the key upcoming dates in the political calendar.

12 April

Parliament is in recess. The cabinet ministers David Lidington and Michael Gove are holding talks with Labour’s John McDonnell to try to reach a compromise on May’s deal. If the sides cannot agree, the government hopes they can at least decide on a process of indicative votes or the path for the withdrawal agreement bill as a way to try to find a parliamentary consensus.

15 April

The UK will need to publish notices for EU elections the prime minister has said she is determined not to hold.

23 April

MPs return to parliament after Easter recess. This is the week in which a new parliamentary process could begin in an attempt to find a consensus – whether by new indicative votes or the government introducing the bill, which MPs could amend, either to add a confirmatory referendum or soft Brexit options such as a customs union.

25 April

The closing date for European parliament elections nominations and candidate lists.

2 May

Local elections take place across England and Northern Ireland. The Conservative party has said it is expecting poor results. The Liberal Democrats are expected to kickstart their contest to replace Vince Cable as leader after the polls.

9 May

EU leaders will hold a summit on the future of Europe in Sibiu, Romania – an event that was supposed to spell out the bloc’s post-Brexit future. May has agreed not to attend.

Mid-May

The approximate time legislation for any second referendum would need to begin passing through the Houses of Parliament, according to Alan Renwick, the deputy director of the Constitution Unit at University College London.

Facebook Twitter Pinterest The UK is due to hold European elections on 23 May if the House of Commons has yet to approve May’s deal. Photograph: Olivier Hoslet/EPA

22 May

The final day on which MPs could pass a withdrawal deal and avoid holding European parliament elections.

23 May

European parliament elections take place across the UK and the rest of the EU, with any campaign likely to be dominated in the UK by smaller protest parties including Nigel Farage’s Brexit party and Ukip, as well as Change UK.

26 May

Results are declared from 10pm, with the Conservatives expecting massive losses. From the limited amount of polling that has been carried out so far, Labour is currently ahead, with significant vote shares likely for smaller parties.

27 May

May would probably need to quit this week in order for a new leader to be in place by summer recess. However, this could technically take place later because only a fortnight would be required for MPs to vote on leadership candidates.

30 May – 11 June

The Commons would probably be due to go on a short Whitsun recess, which would be cancelled if the prime minister is still attempting to pass a Brexit deal, in order to prevent new MEPs from having to take their seats in the European parliament.

20-21 June

EU leaders will assess the progress Britain has made over the past few months at a European council summit.

28-29 June

May, along with EU and world leaders, is due to attend a G20 summit in Osaka. When the prime minister pledged to Tory MPs that she would stand down, she had planned this to be her final overseas summit.

30 June

The date past which May said she would not countenance the UK staying in the EU, and the day before MEPs must take their seats in the European parliament.

Facebook Twitter Pinterest Nigel Farage in the European parliament. New MEPs will take their seats for the first time on 1 July. Photograph: Patrick Seeger/EPA

2 July

New MEPs sit at the inaugural session of the new European parliament.

25 July

The rough date on which the Commons would be expected to rise for summer recess, and the date by which the party would, ideally, like a new Conservative leader to be installed if a contest took place.

Mid-August

The approximate time by which the prime minister would need to call a general election to be held before the article 50 extension expires – in order to meet the requirements of the Fixed-Term Parliaments Act 2011, and also the timetable set out in the Electoral Registration and Administration Act 2013, which requires 25 working days for an election campaign.

25-27 August

The prime minister is due to attend a G7 summit in Biarritz, France.

5-12 September

This is the date on which the Commons would be likely to return from summer recess, bar any early recall of MPs to deal with Brexit crises.

22 September – 2 October

The Labour and Conservative party conferences are held on consecutive weeks.

8 October

The date MPs would return to parliament, 18 working days before the UK would be due to leave the EU.

Facebook Twitter Pinterest The final practical date on which the UK could hold a general election would be 10 October. Photograph: Xinhua/Barcroft Images

10 October

The last practical polling date on which a prime minister could hold a general election or second referendum – the final Thursday before the next European council.

The Electoral Commission is suggesting it would need 10 weeks to organise a poll, as set out in the Political Parties, Elections and Referendums Act 2000, and that there would be a campaign of at least four weeks.

In practice, a change of policy or government this late in the timetable would be likely to require a further extension if a radical change of direction is expected.

17-18 October

EU leaders meet for the final European council summit before the UK’s extension is due to expire.

31 October

The six-month article 50 extension will expire.

12 December

The next date on which Tory MPs can hold a confidence vote in May, if she remains at the helm.