He is well known for telling his fans “thank you very much” at the end of his live gigs but it seems the “King” was just as polite in writing.

A rare thank you letter from Elvis Presley has been discovered by the family of a life-long fan who were clearing out her house after her death.

Written in blue ball point pen on cream paper, the letter says: “Dear Yvonne, thank you so much for the lovely Christmas card and magazine and a Merry Christmas and a Happy New Year!”

The folded letter is signed from “Elvis Presley” and was verified as being written in his hand by experts who could authenticate his signature at the time of writing, and also by examining the type of paper it would have been written on, auctioneer Jonathan Humbert said.

He said: “The family of Yvonne, who was a lifelong Elvis fan, were clearing her estate ­- she lived in the north Bucks area - and found this in her handbag.

“Bearing in mind Elvis died in the late 1970s, it seems it has been in her handbag ever since.

“We think it’s probably circa early 1960s, his writing changed through his career and it became more and more spurious, but it’s authenticated by other signatures of the 1960s.” The rare letter was sent to Yvonne because she had been in communication with Elvis for years and was one of his original fans.

Mr Humbert said the letter, which has no reserve price, is estimated to sell at between £2,500 and £3,000 when it goes under the hammer at the JP Humbert salerooms in Towcester today week. Also included in the auction is a facsimile letter to fans from Graceland. In this, the name Yvonne has been added in what appears to be Elvis’ hand. It was written just before the filming of Blue Hawaii in the early 1960s, Mr Humbert said.

A portrait photo of Elvis with a facsimile signature saying “Thanks Elvis” is included in the sale.