Ruth Davidson has said that she would advise the next Prime Minister not to block a request by Nicola Sturgeon for a second independence referendum in the wake of the vote for Brexit.

The Scottish Tory leader said it was “incredibly premature” and “destabilising” for the First Minister to press for a rerun of the 2014 vote, but she had never thought that one should be denied because she is a “democrat”.

The First Minister said her intervention represents a “major and significant concession” as the Scottish Tories fought the recent Holyrood election campaign pledging to oppose a second referendum and claiming there was no mandate for one.

It is hugely significant as it makes it even more difficult for the next Prime Minister to refuse a rerun. Sources close to the Scottish Tory leader argued that doing so would provoke a massive public backlash in Scotland that could further drive up support for separation.

Ms Sturgeon has said it is “highly likely” there will be another referendum after 62 per cent of Scots voted to Remain in the EU and she has ordered her civil servants to draw up the necessary legislation.

A formal request to 10 Downing Street would require a vote in the Scottish Parliament but there is a pro-independence majority when SNP and Green MSPs are combined. David Cameron agreed to transfer the powers to stage the last referendum after the SNP won a majority in the 2011 Holyrood election.