LONDON -- British Prime Minister Theresa May will chair several hours of cabinet meetings on Tuesday in an attempt to plot a course out of the Brexit maelstrom as she comes under pressure to either leave the European Union without a deal or call an election.

Nearly three years since the United Kingdom voted to leave the EU in a shock referendum result, British politics is in crisis and it is unclear how, when or if it will ever leave the club it first joined in 1973.

May's deal has been defeated three times by the lower house of the British parliament which failed on Monday to find a majority of its own for any alternative to her deal. May is expected to try to put her deal to a fourth vote this week.

The deadlock has already delayed Brexit for two weeks beyond the planned departure date of March 29 and May is due to chair hours of cabinet meetings in Downing Street in a bid to find a way out of the maze.

"Over the last days a no-deal scenario has become more likely, but we can still hope to avoid it," the EU's chief Brexit negotiator Michel Barnier said in Brussels.

"The UK should now indicate the way forward or indicate a plan," Barnier said. "More today than ever."

Barnier said Britain could still accept the stalled deal negotiated by May, reiterating it was "the only way" for Britain to leave the bloc in an orderly way.

If May cannot get her deal ratified by parliament then she has a choice between leaving without a deal, calling an election or asking the EU for a long delay to negotiate a Brexit deal with a much closer relationship with the bloc.

The third defeat of May's withdrawal agreement on Friday - the date the United Kingdom was originally scheduled to leave the EU - has left the weakest British leader in a generation facing a spiraling crisis.

Investors and diplomats are in despair at the chaos and such is the volatility of Brexit news from London that some traders have stepped away from sterling - which has seesawed on Brexit news since the 2016 referendum. Sterling fell on Tuesday.