Opposition Labour Party leader Jeremy Corbyn said he would do everything necessary to prevent Britain leaving the EU without a divorce deal as he prepared to meet senior lawmakers on Tuesday to discuss tactics.

The UK is heading towards a constitutional crisis at home and a showdown with the EU as Prime Minister Boris Johnson has pledged to leave the bloc in 66 days without a deal unless it agrees to renegotiate the Brexit divorce.

Corbyn said an EU exit without an agreement would leave Britain at the mercy of President Donald Trump and US corporations.

"The battle to stop no-deal Brexit isn't a struggle between those who want to leave the EU and those who want continued membership," Corbyn wrote in the Independent newspaper.

"It's a battle of the many against the few who are hijacking the referendum result to shift even more power and wealth towards those at the top. That's why the Labour Party will do everything necessary to stop a no-deal bankers' Brexit."

Britain is on course for a no-deal exit on October 31 unless parliament can stop it or a new agreement is reached with the EU.

The British parliament has rejected three times the withdrawal deal agreed between Johnson's predecessor Theresa May and the EU, deepening a three-year crisis that threatens Britain's status as one of the world's preeminent financial centers.