UK Prime Minister Theresa May tries to talk tough on Scotland

Theresa May. Photo / AP

Theresa May has said Britain is braced for a "defining moment" as it leaves the European Union, as she warned Scottish First Minister Nicola Sturgeon now is "not the time to play politics or create uncertainty".

The British Prime Minister was laughed at by MPs as she told the House of Commons she had been "working closely" with the Scottish Government on preparations for Brexit.

In a swipe at Sturgeon's plans for an independence referendum, May told the Commons: "This is not a moment to play politics or create uncertainty.

"It is a moment to bring our country together, to honour the will of the British people and to shape for them a better, brighter future and a better Britain."

It came as Ruth Davidson, the leader of the Scottish Conservatives, claimed that Sturgeon's position on Scottish membership of the European Union had "unravelled", after she failed to say the nation would remain a member of the EU if it became independent.

Andrew Dunlop, the Government's Scotland Minister, called on Sturgeon to take the prospect of a referendum "off the table".Davidson warned that neither Sturgeon nor her ministers had given a firm commitment that Scotland would be able to remain a member after the United Kingdom leaves.

Nicola Sturgeon. Photo / AP

Speaking in the Lords, he said there was "nothing more calculated" to frustrate a good Brexit deal than another referendum.

May headed off a rebellion by pro-European Conservative MPs yesterday as the Government overturned attempts by the House of Lords to frustrate her plans for a clean Brexit.

Speaking later, May said the Government's bill would get the Royal Assent in the coming days and she would come to the House to announce triggering of Article 50.