Jeremy Corbyn has insisted a no-deal Brexit can be stopped – and MPs will act quickly to try and prevent it when they return from their summer break next week.
The Labour leader made the declaration in the wake of Prime Minister Boris Johnson suspending parliament, a move his critics say is designed to avoid parliament stopping him from pursuing a no-deal divorce.
MPs return to Westminster on Tuesday, with parliament set to be prorogued at some point in the following week until 14 October.
As it stands, the UK is due to leave the EU on 31 October.
Mr Johnson has said the Commons will still have “ample time” to debate Brexit, but the PM has been accused of a “constitutional outrage” and acting like a “tin-pot dictator”.
A petition against the move has gained more than a million signatures, while a number of legal challenges have been launched in the courts.
Mr Corbyn said MPs would pursue legislative means to try and avert a no-deal Brexit.
“We will be back in parliament on Tuesday to challenge Boris Johnson on what I think is a smash and grab raid against our democracy,” Mr Corbyn said.
“He’s trying to suspend parliament in order to prevent a serious discussion and a serious debate to prevent a no-deal Brexit.
“What we’re going to do is try to politically stop him on Tuesday with a parliamentary process in order to legislate to prevent a no-deal Brexit, and also to try and prevent him shutting down parliament during this utterly crucial period.
“The implications for this country are very, very serious.”
And the Labour leader maintained that a possible no-deal Brexit could still be stopped, saying: “We believe we can do it, otherwise we wouldn’t be trying to do it.
“I had a very constructive meeting with the leaders of all the opposition parties in my office a couple of days ago to go through these and we’re going to do everything we can to ensure that parliament is able to assert itself on behalf of the British people to prevent a no-deal exit from the EU.”
And in a sign of the level of cross-party opposition, Mr Corbyn has joined with the SNP, Liberal Democrats, Plaid Cymru, The Independent Group for Change and the Green Party to demand the PM reverse his decision.
In a joint statement, the opposition leaders said: “It is our view that there is a majority in the House of Commons that does not support this prorogation, and we demand that the prime minister reverses this decision immediately or allows MPs to vote on whether there should be one.”
Another of those joining the criticism of the suspension was former justice secretary David Gauke, who told Sky News the decision was “wrong” and sets a “bad precedent”.
Mr Gauke added that Mr Johnson’s move has changed the calculus for opponents of a no-deal exit.
“Quite a lot of us I think were not minded not to rush into such action [trying to stop it], that it would be better to let the negotiations such as they are progress further, if indeed any progress is being made, but at least things would have become clearer as we got towards the end of September,” he said.
“That option doesn’t appear to be there any more.”
Prorogation is essentially a more fancy term for suspending parliament.
It marks the end of a parliamentary session and the action is formally taken by the Queen following guidance from the Privy Council, her body of advisers made up of mostly senior politicians.
It is usually seen as a routine occurrence ahead of a general election or the start of a new parliamentary session.
Prorogation is normally for a short amount of time, no longer than two weeks.
The PM has insisted he is suspending parliament in order to set out his “exciting agenda” in a Queen’s Speech on 14 October.
But critics say doing so at such a politically charged time is unprecedented.
Jacob Rees-Mogg, the leader of the Commons, accused Remain-backing MPs of “crying wolf” with their protests.
Speaking to Sky News, Mr Rees-Mogg described the upcoming prorogation as “routine” and “actually quite boring”.
“But the arch-Remainers who don’t want us to leave the EU have started crying constitutional crisis, but actually they’re crying wolf,” he added.
Meanwhile, legal attempts to challenge the suspension have been launched at the High Courts in London and Belfast, as well as Scotland’s highest civil court.
A cross-party group of around 70 MPs and peers have launched an action at the Court of Session in Edinburgh, seeking an interim interdict which would prevent Mr Johnson taking the option of proroguing until a final decision has been made in the case.
Anti-Brexit campaigner Gina Miller, who previously won a landmark ruling against Theresa May’s government over Article 50, has made an urgent application for a judicial review at the High Court in London.
The legal action in Belfast, launched by prominent victims campaigner Raymond McCord, has been adjourned for 24 hours.