"He was peace-loving, brilliant, funny, opinionated, a treasure - we need people like him today."
Meanwhile, Elton previously confessed he was "quite intimidated" by Lennon.
He said: "We got on like a house on fire. We hung out for a couple of years. I don't know why we got on so well. Sense of humour? I found him very kind, very funny, I don't know why we clicked but we did, and he clicked with my band and the people around me.
"And we had so much fun. I was quite intimidated by him because I knew he was razor sharp and could be abrasive, but that side of him never came out with me, only the kind side and the funny side."
Lennon's last public performance came with Elton in New York's Madison Square Garden in 1974.