London: Opposition MPs from across Britain's divided House of Commons joined forces on Tuesday pledging to legislate against a "no-deal" Brexit instead of calling on a no-confidence vote in the newly installed Prime Minister Boris Johnson when Parliament resumes next week.

With 65 days until Brexit on October 31, the breakthrough marks the first time the six opposition parties have agreed to a combined strategy after failing to agree on an earlier suggestion that Labour leader Jeremy Corbyn be installed as a caretaker prime minister.

John McDonnell, finance spokesman for the British opposition Labour party, signs a declaration following a cross party meeting of members of parliament to oppose any attempts to prevent Parliament from sitting. Credit:Bloomberg

"The attendees agreed on the urgency to act together to find practical ways to prevent no-deal, including the possibility of passing legislation and a vote of no confidence," the parties said in a joint statement after the talks held in Westminster.

The talks between Labour and the Remain-backing Liberal Democrats, Scottish National Party (SNP), The Independent Group for Change, and Green Party, as well as the Welsh Plaid Cymru, came as nearly 200 MPs broke their summer holiday to return to Westminster to sign a pledge vowing "strong and widespread democratic resistance" to any government attempt to prevent Parliament from sitting to force through a no-deal Brexit.