DOWNING Street has rejected claims the Prime Minister is going to break her commitment to making Brexit day fixed in law.

Last week, writing in the Daily Telegraph, Theresa May said she was going to table an amendment to the EU (Withdrawal) Bill that would put the date and time of Britain’s EU departure at 11pm, March 29, 2019, in the statute books.

While some of the more fanatic Eurosceptics in her party thought this a worthwhile idea, the Prime Minister now faces a sizeable rebellion from some of her backbenchers.

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Reports suggest around 30 Tory MPs will vote against the amendment when parliament is asked to back it in the next month.

May’s working majority, thanks to a supply and confidence deal with Northern Ireland’s DUP, is just 10.

However, despite almost certain defeat in the Commons, No 10 said it would not back down.

“As the PM has said, we want to listen to parliament,” the Prime Minister’s spokesman said.

“We are clear, though, on our determination to get the best possible outcome for the UK. Key to doing that is certainty.

“What the amendment does is provide certainty over our position that we are leaving the EU on March 29, 2019. We would encourage all MPs to support it.”

The Westminster Brexit select committee have warned making the date law creates “significant difficulties” and could stop ministers getting a good trade deal.