The UK's former Secretary of State Boris Johnson has started his election campaign for the post of the Conservative Party's leader and the Prime Minister.
Starmer said MPs were forced to act because of suggestions from leadership candidates including Boris Johnson and Dominic Raab that the United Kingdom will leave - come what may - on 31 October, with Raab even suggesting he would be prepared to prorogue parliament to stop MPs efforts to thwart no deal.
"After three years and two missed deadlines, we must leave the European Union on October 31", he said as a heckler yelled "Bollocks to Boris" from outside the Royal Academy of Engineering just off The Mall in central London.
He insisted he was not aiming for no-deal, but said the Government had to show it was serious about leaving if it was to stand any chance of securing concessions from the EU.
For many, the contest for prime minister is his to lose - he has the most declared Conservative supporters in parliament and is widely popular among the party's members, the people who will ultimately choose May's successor.
"It is only responsible to prepare vigorously and seriously for no-deal", he said.
As the result was announced, Tory MPs cheered on the benches.
Johnson said a new government with "new optimism" and "total conviction about the way forward" could find a way to find a compromise, although he gave no detail.
Asked if he could be trusted, Mr Johnson said he could.
Labour said that if passed, the motion, though binding, would not in itself legislate to prevent a no-deal. "I think it will be very hard for friends in Parliament to obstruct the will of the people and simply to block Brexit", Mr Johnson said.
Labour leader Jeremy Corbyn was overheard rebuking MPs, saying that they "won't be cheering in September" as they celebrated the defeat of the motion.
Grieve, who sided with the opposition in the vote, told MPs: "And I simply have to say here and now I will not hesitate to do that if that is what is attempted, even if it means my resigning the whip and leaving the party".
Mr Johnson apologised for "the offence I have caused", but said: "I will continue to speak as directly as I can".
Conservative lawmakers will hold the first of a series of secret ballots on Thursday on the leadership candidates, who also include foreign minister Jeremy Hunt and interior minister Sajid Javid.
One of the reasons the public "feels alienated" from politicians is because "we are muffling and veiling our language", he added.