David Cameron's revelation that he sought help from the Queen ahead of the Scottish independence vote in 2014 has caused displeasure at Buckingham Palace, a source has said.

Axar.az reports citing BBC.

The former PM told the BBC he had asked whether the Queen could "raise an eyebrow" about the prospect of Scotland voting for independence.

The Queen later said people should "think carefully about the future".

Buckingham Palace has made no official comment on Mr Cameron's remarks.

The revelation is made in a two-part BBC documentary in which the former PM reflects on his time in Downing Street.

What was discussed with the Queen's officials was not "anything that would be in any way improper... but just a raising of the eyebrow even... a quarter of an inch", he says.

The former Tory leader also discusses the Scottish referendum in his book, which he has been publicising this week.