File: If no agreement is reached on Wednesday, the legal default is that Britain leaves the EU without a deal on Friday.
LONDON - As British Prime Minister Theresa May scrambles to secure a Brexit extension at Wednesday's crucial EU summit, where is the whole process heading?
Here is what could happen:
- No-deal Brexit on April 12 -
But the EU appears to be more keen on a longer "flextension" of around a year.
If no agreement is reached on Wednesday, the legal default is that Britain leaves the EU without a deal on Friday.
The EU has already granted one delay -- the original deadline was March 29 -- and EU leaders will ask May to explain what another postponement would achieve.
Economists warn a no-deal Brexit could generate economic shockwaves on both sides of the Channel and cause severe delays at border points, despite preparations to mitigate these risks.
- Leave with changes to May's deal -
After failing three times to get her deal through parliament, May is currently locked in talks with the opposition Labour Party -- who favour keeping closer ties with the EU -- to try and break the impasse.
Labour is demanding Britain remain in a customs union, angering the rank-and-file in May's Tory party.
If they agree a deal, Brexit could still happen before Britain has to take part in European Union elections on May 23.
The withdrawal agreement allows for a long transition period and time for trade ties to be negotiated.
The EU has ruled out any changes to it but has said it could speedily rewrite the political declaration -- an accompanying document on future trade ties.
In a desperate gamble to get the deal over the line, May even told her MPs that she would resign before the start of full-blown trade negotiations with the EU if they backed it, but it still failed.
- New plan, long Brexit delay -
If no deal is agreed in the coming days, Britain will likely face a delay of up to a year, which would entail it holding European Parliament elections.
The European Commission, the EU's executive arm, has advised EU leaders that this longer extension should be at least until the end of 2019 and possibly much longer to allow for a proper change in Brexit strategy.
Under the "flextension", Britain could leave the EU once it found a plan commanding domestic support, but a longer delay would open up options such as holding a general election, a leadership election to replace May or, perhaps, a second referendum.
A general election would reset parliament, and a clear outcome with a government majority could result in a much stronger administration.
But there is a danger it could result in the same situation as now with no one party holding a majority.
And for both major parties, finding a definitive manifesto position on Brexit that all their MPs can commit to could prove a challenge.
A long delay also opens up the possibility of another referendum.
The Labour Party is reported to be pushing for one in return for approving May's deal.