Jeremy Corbyn has demanded Boris Johnson "resign now" in a damning Labour conference speech.
Party members erupted into cheers of "Johnson out!" as the Labour leader said Mr Johnson was "not fit to be Prime Minister" after losing a Supreme Court showdown.
Opening his 42-minute annual address in Brighton, Mr Corbyn declared: "He will never shut down our democracy or silence the voices of us, the people."
He added: " Boris Johnson has been found to have misled the country. This unelected Prime minister should now resign."
It came as Mr Corbyn hastily rewrote, cut down and moved forward his conference speech by a day after the Supreme Court ruled Parliament could sit again from 11.30am tomorrow.
Despite demanding an election, Labour's leader stopped short of saying the party will table a vote of no confidence in the government thisweek.
Instead he said an election should wait until the threat of a no-deal Brexit on October 31 is removed.
He told delegates in Brighton: "This crisis can only be settled with a general election. That election needs to take place as soon as this government’s threat of a disastrous No Deal is taken off the table."
It comes after the Supreme Court - prompting the Commons to resume sitting at 11.30am tomorrow.
In a historic judgement that will go down in British legal history, 11 justices said it was unlawful and "extreme" to shut down the Commons for five weeks just before Brexit.
Declaring the prorogation of Parliament "unlawful, void and of no effect", Supreme Court President Lady Hale quashed the Queen's order to shut down the Commons and declared: "Parliament has not been prorogued."
Jeremy Corbyn hastily rearranged his Labour conference speech to 4pm today to get back to Parliament in time.
And he stripped out nearly all policy announcements in order to focus on the crisis in democracy.
He told members: "The Prime Minister acted illegally when he tried to shut down opposition to his reckless and disastrous plan to crash out of the European Union without a deal.
"But he has failed."
Mr Corbyn added: "Boris Johnson has been found to have misled the country. This unelected Prime Minister should now resign.
"That would make him the shortest serving British prime minister in history and rightly so."
Mr Corbyn told cheering members the Prime Minister was "part of an elite that disdains democracy".
He said: "Let me quote the Supreme Court's conclusion: 'Unlawful, null and of no effect and should be quashed' - they've got the prime minister down to a tee."
Mr Corbyn was introduced to thousands of delegates by The Voice winner Jermaine Jackman - who sang a change was due to come before Labour's leader walked on stage.
Labour's leader kept just one new policy announcement in the speech.
He - by using compulsory licensing to secure generic versions of the drugs.
The rest of his stripped-back speech was a greatest hits of previously announced pledges - including free prescriptions for all in England, a National Care Service and nationalising water, mail and rail.
He said Labour would put the issue of Brexit back to the people in a referendum - allowing them to vote between a "credible" leave deal and Remain.
"As a Labour Prime Minister I pledge to carry out whatever the people decide," he said.
He also:
- Accused Mr Johnson of playing on people's fears by comparing veiled Muslim women to "letterboxes or bank robbers"
- Promised a green industrial revolution with three new battery plants in South Wales, Stoke-on-Trent and Swindon
Insisted Labour's Brexit policy, which involves staying neutral, fighting an election, negotiating a Brexit deal for three months, then holding a special conference to decide how to campaign in a second referendum, was "not complicated"
Warned against sending troops to Saudi Arabia, claiming British actions in the Middle East had resulted in "spreading conflicts rather than settling them".
Mr Corbyn declared "we stand for the 99%" and said he could sum up the Tories in five words: "A harsh and uncaring ethos".
And after a conference plagued by gossip of his possible resignation in future, the 70-year-old reflected on his style of leadership.
He admitted he was "not there on a personal power trip - shadow cabinet can confirm that".
And he said: "I have what might be considered a different view of leadership from the one people are used to.
"I do believe leaders should have strong principles that people can trust. But leaders must also listen and trust others to play their part.
"Because there are leaders in every community driving change. Many of them would never dream of calling themselves leaders, but they are.
"I’m thinking of the mother who campaigns on behalf of the residents in her block to get the damp removed, and the fast food worker organising their colleagues to demand a living wage.
"It’s those leaders Labour is now working with and supporting. Because our philosophy is to trust the people and give them the power to make change in every community and workplace, not hand more power to politicians.
"And that’s why, if the British people elect a Labour government in the coming election I will be proud to be your Prime Minister. Because I will be a different kind of Prime Minister."
This year's conference was overshadowed by two rows - first a failed bid to oust Tom Watson as deputy leader, and then a row over Labour's Brexit policy.
A bid to turn Labour into a 'Remain party' against Jeremy Corbyn's will was defeated on a show of hands last night.
Finishing his speech, Mr Corbyn said it was time to build a country "fit for the next generation".
"A country where young people don't fear the future... but a country and a society where our young people can look forward with confidence and hope."
He added: "The tide is turning. The years of retreat and defeat are coming to an end.
"Together, we can take on the privileged, and put the people in power."
And he told party members: "Go forward to win an election for the people of the country."
