David Cameron said that he did not care about Scotland days after the country voted to remain part of the union, according to a former Liberal Democrat MP.

In a new book about the coalition, ex-Liberal Democrats schools minister David Laws claims that the Prime Minister told Nick Clegg that Scotland was 'Labour's problem' after the independence referendum.

The section in the book written by Mr Laws said: "Nick Clegg warned that the referendum aftermath was in danger of becoming a complete disaster. He said bluntly that the Prime Minister was in danger of guaranteeing the break-up of the UK, with the only beneficiaries being the SNP.

"'Look Nick'", said David Cameron impatiently, "I just don't care. We've only got one Conservative MP north of the Border. Let Labour sort it out. It's now their problem.

Read more: Cameron urges Scots - don't rip apart UK and break my heart

"Nick Clegg and Danny Alexander were both furious. 'I used to disagree with the Conservatives but at least respect them,' Nick Clegg told me a week later. 'But now I have contempt for what they have done. It is all so bloody short-termist and short-sighted."

HeraldScotland:

The claims, which completely contradict Mr Cameron's public stance at the time of the referendum, have been dismissed by Downing Street as 'tittle-tattle'.

Mr Cameron's spokesperson said: "I don’t recognise those comments at all.

"The PM has been very clear in his belief that the United Kingdom is stronger together and he continues to do all he can to support that and while delivering on the comments the Government has made in regards to devolution."

Mr Cameron made an emotional plea to Scottish voters to save the Union in the run-up to the referendum on September 18.

Read more: Cameron insists there will not be a second referendum on Scottish independence

He said: "I speak for millions of people across England, Wales and Northern Ireland – and many in Scotland, too, who would be utterly heart-broken by the break-up of the United Kingdom.

"We are a family. A family is not a compromise, or a second best, it is a magical identity, that makes us more together than we can ever be apart so please – do not break this family apart."

However, Labour and the SNP said the revelations had ''blown Ruth Davidson's election campaign out of the water'.

Read more: Cameron's referendum challenge to Salmond

An SNP spokesperson told The Times: "Ruth Davidson's election claims are badly undermined by the relevation that her boss simply 'doesn't care about Scotland'."

The book, Coalition: The Inside Story of the Conservative-Liberal Democrat Coalition Government, also claims that Mr Clegg said Mr Cameron and George Osborne would 'sell their mothers to stay in Downing Street'.

Scots will go to the polls in the Holyrood elections on Thursday, May 5.