Elton John has opened up about his interactions with the "King of Pop" Michael Jackson and called him "disturbing to be around".

In his highly anticipated memoir "Me", Elton John writes that though Jackson was the "most adorable kid" one could imagine, he later began distancing away from reality. He first met MJ when the latter was 14 after one of his shows in Philadelphia.

"But at some point in the intervening years, he started sequestering himself away from the world, and away from reality the way Elvis Presley did," the 72-year-old singer writes in the book.

"God knows what was going on in his head, and God knows what prescription drugs he was being pumped full of, but every time I saw him in his later years I came away thinking the poor guy had totally lost his marbles," John wrote, reports Independent.

The singer further explains that the pop-star was "genuinely mentally ill" and a "disturbing person to be around". "It was incredibly sad, but he was someone you couldn't help: he was just gone, off in a world of his own, surrounded by people who only told him what he wanted to hear," John writes in the tell-all memoir.

The "Rocket Man" singer also said that for some reason, Jackson was not able to cope with adult company at all. He recalled that at a party he had hosted with future husband David Furnish, Jackson left the party without having food, and was later found in the company of John's housekeeper's 11-year-old son, playing video games in the housekeeper's cottage.

Elton John
Sir Elton John has a performance of two songs before holding a press conference in New York January 24, 2018. Getty

Jackson was known for his close friendships with a number of children when he was an adult. After MJ's death on June 25, 2009, his legacy took a downturn as some accused him of molesting children.

The autobiography of John titled "Me" published by Macmillan is scheduled to release on Tuesday. The singer has written about a number of other interesting interactions in his memoir, which also includes his troubled relationship with his mother as he says he is glad she never met his children.