A draft letter which exposed the tensions between John Lennon and Paul McCartney, thought to have been written in the 1970s, is expected to reach £40,000 when it goes to auction.
The direct two-page letter, written on personalised stationery which features a picture of Lennon and his wife Yoko Ono, is addressed to Paul McCartney and his wife Linda.
"Do you really think most of today's art came about because of the Beatles? I don't believe you're that insane - Paul - do you believe that? When you stop believing it you might wake up!" Lennon writes.
The letter, which is expected to reach between £26,000 and £39,000, will go on sale in an online auction on May 30.
A similar letter by Lennon to the McCartneys, discussing the end of The Beatles, was auctioned at Christie's in London last October but failed to reach the £63,000 reserve price.
- Watch: Paul McCartney and John Lennon discuss their careers in 1968: