Lawmakers voted by 328 to 301 for a motion put forward by opposition parties and rebel lawmakers in Johnson’s party – who had been warned they would be kicked out of the Conservative Party if they defied the government.

More than three years after the United Kingdom voted in a referendum to leave the European Union, the defeat leaves the course of Brexit unresolved, with possible outcomes still ranging from a turbulent ‘no-deal’ exit to abandoning the whole endeavour.

Tuesday’s victory is the first hurdle for lawmakers who, having succeeded in taking control of parliamentary business, will on Wednesday seek to pass a law forcing Johnson to ask the EU to delay Brexit until Jan 31 unless he has a deal approved by parliament beforehand on the terms and manner of the exit.

The Conservative rebels who now face expulsion from the party included Nicholas Soames, the grandson of Britain’s World War Two leader Winston Churchill, and two former finance ministers – Philip Hammond and Kenneth Clarke.

“I don’t want an election, but if MPs vote tomorrow to stop negotiations and compel another pointless delay to Brexit, potentially for years, then that would be the only way to resolve this,” Johnson told parliament after the vote.

“I can confirm that we are tonight tabling a motion under the Fixed Term Parliament Act.”

In a historic showdown between prime minister and parliament, Johnson’s opponents said they wanted to prevent him playing Russian roulette with a country once touted as a confident pillar of Western economic and political stability.

They argue that nothing can justify the risk of a ‘no-deal’ Brexit that would cut economic ties overnight with Britain’s biggest export market and inevitably bring huge economic disruption.