LONDON (Reuters) - A group of British lawmakers said on Tuesday they would try to pass a law which would force Prime Minister Theresa May to seek a delay to Britain’s departure from the European Union and thus prevent a potentially chaotic no-deal exit on April 12.

A person walks past an EU and a British flag in London, Britain, April 2, 2019. REUTERS/Hannah Mckay

Parliament has failed so far to find a majority for any alternative to May’s thrice-defeated deal.

Leaving the EU without a deal on April 12 is the default legal option if Britain cannot present another viable option to EU leaders holding an emergency Brexit summit on April 10.

“We are now in a really dangerous situation with a serious and growing risk of no-deal in 10 days’ time,” said opposition Labour lawmaker Yvette Cooper, who has proposed the legislation alongside eleven others from several political parties, including members of May’s Conservatives.

“The Prime Minister has a responsibility to prevent that happening ... If the government won’t act urgently, then parliament has a responsibility to try to ensure that happens even though we are right up against the deadline.”

The EU would have to agree to any further delay to the Article 50 negotiating period, and have said Britain would need to give a reason for the delay.

The lawmakers said it would be up to the government to decide how long to propose as a delay, although the draft legislation notes that both parliament and the EU could propose a different length of extension.

Conservative lawmaker Oliver Letwin, who led the process of so-called indicative votes on alternative Brexit options, said the draft legislation was “a last-ditch attempt to prevent our country being exposed to the risks inherent in a no deal exit.”

“We realise this is difficult. But it is definitely worth trying,” he added.

Lawmakers are due to take control of parliamentary time on Wednesday and Cooper told BBC Radio they would use to carry out the process that needs to be completed before the bill is debated. The plan is to debate the bill on Thursday.

Pro-Brexit Conservative Bill Cash told parliament seizing control in this way was a “a reprehensible procedure”.

“It is unconstitutional, it is inconceivable that we should be presented with a bill which can be rammed through in one day,” he said.

Parliament’s speaker John Bercow said it was not unusual for government legislation to be passed by the House of Commons in a single day.