MPs have easily passed a backbench amendment which seeks to block any attempt by a future government to prorogue parliament to ensure a no-deal Brexit, in what is likely to be seen as a pre-emptive strike against Boris Johnson's authority.
The amendment, tabled by a cross-party group led by Labour’s Hilary Benn and the Conservatives’ Alistair Burt, passed by an unexpectedly high margin of 41 votes, with 315 MPs backing it and 274 opposed.
One of those to support the measure was culture, media and sport minister Margot James, who resigned from her post to do so. Philip Hammond, the chancellor, was among a reported series of ministers who abstained, despite a maximum three-line whip.
Mr Johnson, the clear favourite to be declared winner of the Conservative leadership contest against Jeremy Hunt next week, and thus replace Theresa May as prime minister, has repeatedly refused to rule out using prorogation to ensure a no-deal Brexit on October 31st.
The scale of the victory highlights the struggle he will have to impose his will over Brexit, or other subjects, on a Commons without a Tory majority, and where much Conservative internal discipline has broken down.
The Benn-Burt plan beefs up earlier amendments made to an otherwise-technical Northern Ireland Bill designed to thwart prorogation, though experts remain split over whether MPs can definitively block this.
When the Bill was first considered by the Commons, MPs passed by a single vote an earlier amendment by Tory MP Dominic Grieve intended to make it more difficult for a future government to prorogue, or suspend, parliament to prevent MPs blocking no deal.
Mr Grieve’s first amendment would require a minister to report to the Commons every two weeks until December on the progress of talks on restoring the Northern Ireland Assembly – though it remained unclear whether this could be done as a written report, meaning the chamber would not necessarily have to sit.
This was later changed via another amendment in the Lords, tabled by David Anderson, a former independent reviewer of terror legislation, with support from Labour and the Liberal Democrats.
The new Lords amendment would ensure that the fortnightly reports demanded by Grieve’s amendments would have to be debated within five calendar days of being produced, thus necessitating that the Commons sat.
When the Bill returned to the Commons Mr Grieve then added another tweak via a last-minute amendment, intending to increase the power to block prorogation even more.
It specified that if ministers could not meet the obligation to update the Commons because it is prorogued or adjourned, parliament must meet on the day necessary to comply with the obligation, and for the following five weekdays.
The Bill to which all these were attached was initially a simple one intended to delay elections and budgets for the long-suspended Northern Ireland Assembly and Executive.
When it was first in the Commons last week, MPs overwhelmingly passed amendments to it extending the rights of same-sex marriage and abortion to Northern Ireland, the only places in the UK where they are not allowed.
New deal
Meanwhile, David Lidington, the de facto deputy prime minister, told an instalment of BBC’s Panorama that the EU offered to put Brexit on hold in 2018 for five years and proposed a “new deal for Europe”.
He said: “[The European Commission’s top official] Martin [Selmayr] sort of said: ‘Look, why don’t we have a deal whereby we just put all this on ice for five years? . . . Let’s see how things go, let’s get the UK involved with France and Germany, let’s see how the dust settles and let’s talk about whether we can come to a new deal for Europe.’”
The EU’s chief Brexit negotiator, Michel Barnier, told the same programme that Theresa May and her ministers “never” threatened during negotiations with the EU to take the UK out of the bloc without a deal.
Mr Barnier, who insisted the withdrawal agreement was the only way to leave in an “orderly manner”, said the UK would have to “face the consequences” if it crashed out.
In the interview with Panorama – recorded in May, before the start of the Conservative leadership contest – Mr Barnier was asked if the prime minister or her negotiators ever mentioned or threatened a no-deal exit.
He replied: “No, no, I never listened to such a sentence. Never.”
He added: “We have put in the document [the withdrawal agreement] with the UK – not against the UK, with the UK – the legal answers to each and every point of uncertainty created by Brexit.
“That is the point.”
Downing Street appeared to refute the remarks, saying: “The prime minister was clear both in public and in private that the UK was prepared to leave without a deal.”
Mr Selmayr told the same programme the UK was unprepared to leave the EU without a deal.
“We have followed the British debate and the British preparations very, very closely and we have seen what has been prepared on our side of the border for a hard Brexit – we don’t see the same level of preparation on the other side of the border.
"You would have to establish a lot of authorities in the United Kingdom that you don't have at this moment in time so I think the European Union have been very well-prepared for that – we could live with a hard Brexit.
“We don’t think the same level of preparation is there on the UK side.” – Guardian/PA