The nasty letter John Lennon wrote to Paul McCartney in the '70s has sold at auction after 17 days of bidding ... with the winner coughing up some serious dough for the piece of Beatles drama.
Dylan Kosinski, a rep for Gottahaverockandroll Auction House, tells TMZ ... the Lennon letter sold on Saturday for a total of $70K -- a winning bid of $56K, plus the buyer's premium of $14K -- the fee for participating in the auction.
As we reported, John fired off a letter to Paul days after an interview critical of him and The Beatles appeared in a November 1971 issue of British music magazine Melody Maker, and John's reply is mostly scathing ... but also thoughtful and pleading.
John's frustration with Paul is clear from the jump ... telling Paul he's ungrateful for all the money he's getting from The Beatles.
As the 3-page letter rambles on, John takes issue with Paul dismissing his song "Imagine" and berates Paul for allegedly threatening to "get us whatever the cost" -- "us" referring to the rest of The Beatles.
The piece was estimated to fetch between $30-40K ... we're told there were 11 bidders gunning for the letter, with a total of 14 bids in 2 1/2 weeks' time.
It's worth noting ... Peter Jackson's Disney+ doc, "Get Back," framed John and Paul's relationship as friendly, but this letter shows just how much their friendship frayed after 1970.