© Getty ImagesAnti-Brexit protesters outside parliament. The EU's chief negotiator, Michel Barnier, said on Thursday no deal was the 'most plausible outcome'.
It was by all accounts a "sobering" meeting between the 27 EU ambassadors, the bloc's chief negotiator, Michel Barnier, and the most senior of its officials, Martin Selmayr, on Thursday afternoon. No deal was now regarded as the "most plausible outcome", Barnier warned. But the decision by the EU's leaders at the summit in Brussels last week to give Theresa May an unconditional article 50 extension pushing the Brexit cliff-edge from 29 March to 12 April leaves all scenarios open.
Related: Third Major defeat for May as MPs reject her EU withdrawal agreement © Reuters
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Here are the possible next steps:
Withdrawal agreement is rejected but Downing Street is unable to indicate a way forward by 12 April
The leaders said they would consider a lengthy extension to article 50 if the withdrawal agreement was rejected at the third time of asking. They said, however, that they would expect "the United Kingdom to indicate a way forward" before 12 April "for consideration by the European council". If Downing Street is in complete paralysis or it rejects any solution that might emerge from the Commons second session of indicative votes on Monday, then the EU's leaders will be in a spot. They will likely call a summit on 10 April come what may. The decision will be whether to cut the UK loose, with the expectation that the concomitant no-deal chaos will drag the UK government swiftly back to the negotiating table, or possibly appeal to MPs over the heads of the government. Brussels could offer a lengthy extension with conditions - and let parliament decide what to do next. EU countries do not want to be on the wrong end of the inevitable blame game.
Leave vs Remain: Images of a divided nation (Photos)
The Commons backs a softer Brexit
If the Commons was to back a permanent customs union in its indicative votes next week, the EU could "within days" revise the political declaration, the non-binding outline of the future relationship, to set the two negotiating teams on that course. The wording will not be detailed. The negotiations over the terms of a customs union will be hard-fought when they come. Labour has said it would want the British government to have a say in EU trade policy in such a situation. This is likely to have a pretty messy collision with reality - but that is for a later date once the UK is out. In such a scenario, it is still feasible that the withdrawal agreement and political declaration are ratified by parliament within weeks, and the UK leaves the EU by the 22 May.
The Commons backs a second referendum or the prime minister calls a general election
Both of these scenarios would require a lengthy extension beyond elections for the European parliament. At the summit on 10 April, leaders would decide on the length. Any extension to article 50 in this scenario would be no shorter than nine months, taking Britain's membership of the EU up to 31 December 2019. A full year is far more likely and anything up to 21 months is possible, keeping the UK in the bloc until 2021.