Boris Johnson is threatening to sabotage the EU to make it cave in on a Brexit deal – or reject MPs’ plan to stop the UK crashing out of the bloc.

In a dramatic escalation of its battle with Brussels, Downing Street believes it has devised a way out of the crisis to make the EU no longer “legally constituted”, paralysing its decision-making.

The extraordinary plan would see the UK refuse to appoint a commissioner, putting the EU in breach of its own legal duty for all 28 member states to be represented on its executive branch.

No 10 believes the UK would be “disrupting” Brussels life to such a degree that member states will then make it clear they will refuse to grant an Article 50 extension – even if asked for.

A source said: “We will turn the pressure onto the EU to show how difficult it will be for them if the UK is still hanging around.”

The aim is to force an acceptable Brexit deal, but the source added: “If they won’t negotiate a deal, it would be ideal if they would kick us out.”

The threat to bring the EU to a standstill is a hugely controversial attempt to break free of the ambush which saw MPs move to block a no-deal – while also denying Mr Johnson the general election he craves.

The prime minister is under pressure to come up with a “plan B”, to avoid the unenviable choice of breaking the law by refusing to seek an extension, or quitting No 10 after six weeks in office.

The prospect of him ignoring the law instructing a Brexit delay triggered furious criticism yesterday, after Mr Johnson said he would only apply “in theory”.

David Lidington, Theresa May’s de-facto deputy, sacked by her successor, warned of a “really dangerous precedent” that would bolster the rise of authoritarian leaders across the globe.

“It is very important, at a time when, around the world, we are seeing people in other countries holding up alternatives to rule of law and democratic government, that British governments do always demonstrate that they comply with the law,” he said.

Michael Heseltine, the Tory grandee and supporter of the People’s Vote campaign, told The Independent: “It is absolutely extraordinary that a Conservative prime minister needs to be reminded by a colleague that the British government should follow the rule of law and not act in a way which emboldens dictators and strong-arm populist leaders to undermine democracy.”

Jeremy Corbyn said: “It’s a chilling message for people in our country and a dangerous example to would-be autocrats and hard-right leaders across the world.”

And Jo Swinson, the Liberal Democrat leader, said: “Boris Johnson’s actions show a fundamental disregard for democracy. He is simultaneously horrifying our allies and delighting right-wing populist leaders around the world.”

However, No 10 rejects the “false choice” between resigning or law-breaking, placing its faith in the new aggressive stance with Brussels to allow him to escape either fate.

Article 17 of the Treaty on European Union means the EU will “not be legally constituted on 1 November” – the date the new European Commission takes office – without a UK commissioner, it says.

Brussels could try to reduce the number of commissioners from 28, one for each state, but the UK would have a veto which it would use unless the EU bent to its will.

No 10 accepts Mr Johnson would be breaking the law if he refused to seek the extension parliament will demand – but believes events will not reach that stage, because the EU would be forced to back down first.

The move is being revealed after a day which saw:

* A former director of public prosecutions warn Mr Johnson is heading for prison if he breaks the law and defies parliament by still pursuing a no-deal Brexit

* Groups of pro and anti-Brexit protesters clash violently on Parliament Square, forcing the police to intervene

* The head of the Conservatives for a People’s Vote group cut up his Tory membership card, declaring the party under Mr Johnson is “no longer for me”

* Philip Hammond, the former chancellor, expelled from the party for his Brexit revolt last week, reveal he is taking legal advice over his ejection

* No 10 begin negotiations with TV bosses for live TV election debates, believing Mr Corbyn will “run scared”

The no-deal blocking bill – to become law on Monday – will give the prime minister only until 19 October to pass a deal before he must seek an extension to at least 31 January.

One possibility being floated is for him to refuse to send the legislation to Buckingham Palace for royal assent, to dare the Commons to bring him down.

Alistair Burt, another of the 21 expelled rebels, told The Independent that No 10 had “lost their minds” and called for Dominic Cummings, Mr Johnson’s controversial chief aide, to be sacked.

“We are losing grip completely. This week has been the most disastrous I have experienced in 32 years in parliament. They are not behaving rationally,” Mr Burt said.