What is the state of play with MPs plotting to block a no-deal Brexit?

A law to prevent a no-deal Brexit seems more likely than it did, and a vote of no confidence to bring down Boris Johnson seems less likely, but the mood among MPs will be volatile when parliament reconvenes on 3 September.

Jeremy Corbyn, the Labour leader, has invited the leaders of other opposition parties, and several prominent Conservative opponents of a no-deal Brexit, to a meeting tomorrow.

His invitation had a mixed response. Dame Caroline Spelman, the Tory former cabinet minister who led opposition to no deal under Theresa May, said she wasn’t interested and that she supported Boris Johnson’s approach.

Nick Boles, the former Tory MP now sitting as an independent, said he couldn’t be there but urged Corbyn to focus his efforts on legislation rather than a confidence vote.

And that seems to be what a group of ministers who recently left the government are doing. Philip Hammond, Greg Clarke, David Gauke and Rory Stewart are said to be using their contacts to discuss with European leaders the length and terms of any Brexit extension.

This is significant because, if the EU is prepared to grant a further extension, the most certain way of making it happen would be for the terms to be set out in advance of the EU summit on 17 October. Johnson could then be instructed by an act of parliament to accept the terms offered.

It would be difficult to pass such an act against the wishes of the government, but Yvette Cooper, the Labour former cabinet minister, showed that it was possible in April, when she passed a law requiring Theresa May to seek an extension.

The weakness of that act was that it could not require the prime minister to agree to an extension, because the EU had not decided at that stage how long one should be. Hence the importance of early agreement among EU leaders on the terms.

As things stand, this legislative route looks as if it is a surer way of blocking a no-deal Brexit than the idea of replacing Johnson with a caretaker prime minister. That plan involves opponents of no deal agreeing on a temporary prime minister who would negotiate an extension and preside over a general election.

So far, MPs have been unable to agree who that temporary prime minister should be. Corbyn said it should be him, while Jo Swinson, the new leader of the Liberal Democrats, said it should be Ken Clarke or Harriet Harman. Last week, Caroline Lucas, the Green MP, wrote to Corbyn saying she was prepared to support him, but “if he cannot gain the support of a sufficient number of colleagues across parliament, I hope he will be prepared to back another MP from his party, or another, who can”.

Even if opponents of no deal can unite behind a single candidate, however, it will be hard to muster the votes needed to force Johnson out of office. Several Tory MPs who are strongly opposed to no deal say they will not go as far as to vote for a motion of no confidence in Johnson’s government.

Hence the intense discussions about the alternative plan of backbench legislation to block a no-deal Brexit. But, as Nick Boles says, this will take time, and, if MPs opposed to no deal are serious, they cannot afford to wait until October.