The Conservative leadership race is entering its final phase, clearing the way for a new prime minister to pick up the formidable challenge of delivering Brexit.
Set to be decided in the coming weeks is whether Boris Johnson or Jeremy Hunt, the two remaining contenders to take over from Theresa May in Downing Street, will be prepared to lead the UK out of the EU without a deal.
Here is a road map of some of the big moments ahead as Britain and the EU head towards the new Brexit deadline of October 31.
New European Parliament meets
The UK’s failure to leave the EU on schedule means that British MEPs will return to Brussels.
MEPs voted last year on a plan to abolish 46 of the UK’s 73 seats and redistribute the remaining 27 to member states that have complained of being under-represented. France and Spain were in line to be the biggest winners, gaining five seats each, with another three for Italy and the Netherlands.
But UK participation means the seat redistribution is on hold. There will be 751 MEPs in the new parliament. Parliamentary insiders say the body will revert to the smaller seat distribution when the British are formally out.
That would mean maintaining waiting lists of prospective MEPs in France, Spain and other countries, who will only take up their seats after Brexit.
New Tory leader
The result of the run-off between Mr Johnson and Mr Hunt for the Tory leadership will be declared on this day, setting the stage for the next phase of Britain’s Brexit saga.
Both candidates have said they want to renegotiate Mrs May’s deal with Brussels — which the EU insists it will not reopen. But Mr Johnson has taken the more aggressive stance of the two, maintaining that the UK will leave on the scheduled date of October 31, with or without a deal, “do or die”.
New prime minister
Mrs May is set to complete her long goodbye from Downing Street the day after the Conservative leadership election result. This would allow her to make one final appearance at prime minister’s questions before travelling to Buckingham Palace to bid farewell to the Queen. Her successor would then enter Number 10 and is likely to make a brief speech by which his time in office may be judged in future years.
House of Commons recess
MPs worried about the course of government policy under the new prime minister will have precious little time to act before the Commons goes on its summer holiday.
If the Labour party plans to put forward a motion of no confidence in the new premier before the summer break, it must do so on this day, July 25, after which parliament will be adjourned.
This date is set to be the start of what could be one of the Commons’ most momentous sessions for years.
If the new prime minister is set upon leaving on October 31 without a deal, a battle with pro-EU MPs is a virtual certainty. Given the Conservatives’ lack of a majority, it could be a titanic struggle.
September 29-October 2
Conservative party conference
This will be the first such outing for the new prime minister. Mrs May set the course for her premiership at her first conference speech as prime minister when she in effect pledged to pursue a hard-Brexit policy.
By promising to end the free movement of EU citizens and escape the sway of the European Court of Justice, she left no other viable avenue open than an exit from the EU’s single market.
The next Tory leader’s address at the Conservative conference could be more important, with Brexit day barely a month away.
This is the last scheduled EU summit before the UK’s departure day. Like the bloc’s gathering in March, it could be hijacked by Brexit.
The new deadline — Brexit day?
This day could go down in history. It is the new date when a no-deal Brexit could take place, after the EU’s decision to delay the UK’s departure twice, from March 29 and April 12.
EU leaders insist that, by this point, the UK must choose whether to ratify the exit treaty, opt for a no-deal Brexit, or cancel its departure.
The deadline is not arbitrary. As Mr Macron pointed out, the end of October begins a new five-year political cycle in Brussels, as a new European Commission takes office.
The likelihood of a departure without a deal has gone up, given Mrs May’s three failures to get her deal through the House of Commons; and the hard Brexit stances of many of her potential successors.
But the possibility of another delay cannot be excluded.
If and when MPs vote for an exit agreement
To ratify any Brexit deal, MPs would still have to pass the UK’s agreement with the EU into law, in less contentious form than the Withdrawal Agreement bill whose unpopularity finally sunk Mrs May’s premiership
A deal must also be approved by the European Parliament in a plenary vote. Any legally questionable elements of the withdrawal treaty could also be referred to the European Court of Justice by MEPs. EU member states must also give the deal final approval in a ministerial meeting.
After Brexit day
Trade talks and transition
If Brexit finally takes place with a deal, fully fledged trade talks can begin between the UK and the EU. While Britain remained a member state, such talks were not permitted under EU law.
Under the deal reached in principle in 2018, this is when the transition period until December 2020 should begin. During this time most aspects of UK membership of the EU will remain in place, including free movement across borders and membership of the customs union and single market. But Britain will no longer have a vote.
December 31, 2020
An end to transition?
Although Britain’s departure from the EU has been delayed, the December 31, 2020 date for the end of the transition has not been changed, meaning that there will be less time to conclude a final deal and for businesses and other groups to adjust.
Even when a 21-month transition from March 2019 was in prospect, rather than a 14-month one from October 2019, many negotiators doubted that a full UK-EU trade deal would be agreed by this point, or for some time to come, given the protracted nature of such talks. However, the treaty also establishes that the transition can be extended up to December 31, 2022.
December 31, 2022?
Entering the backstop
The provisional withdrawal treaty makes clear that if, at the end of the transition, no deal is in place to avoid a hard border with Northern Ireland, the so-called backstop will automatically kick in.
This will keep the entire UK in a “temporary” customs union with the EU, although Northern Ireland will be more deeply integrated into the bloc.
Brexiters are deeply opposed to the backstop plan, arguing that it imperils the integrity of the UK, increases Brussels’ powers over Britain on issues such as tax, state aid and labour and environmental regulation, and provides no guaranteed date for departure.
Many business leaders suggest that the “maximum facilitation” plan favoured by some Brexiters, which would rely on advanced technology to speed up customs clearances — and so exit the backstop — would need years to put in place, delaying “full Brexit” until deep into the 2020s.
A less ambitious “fast-track” system on the US-Canada border took decades to develop and billions of dollars in investment.
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