Prime Minister Theresa May yesterday said it was up to MPs to decide whether Britain leaves the European Union next March with no deal despite the potentially catastrophic impact.

Speaking to a parliamentary committee, May was asked several times whether she would personally allow a disorderly Brexit to happen if -- as looks increasingly likely -- MPs vote down the deal she has struck with the EU.

May answered: "It will be a decision for parliament... I've negotiated what I believe truly to be a good deal for the UK."

She also rejected calls for either a second referendum on Brexit or to delay Britain's departure if the deal is rejected in the December 11 vote.

"We would simply find ourselves in a period of more uncertainty and division," she said, adding: "It is absolutely important that we deliver on the vote that people gave."

The prime minister was also asked repeatedly whether she had a back-up plan.

"I think it is important members of parliament focus on the nature of this vote. This is an important point in our history," she said.

She added however that if the deal is rejected, "some people would need to take some practical steps in relation to no deal".