Record producer Sir George Martin, known as the "Fifth Beatle", has died.
Breaking the news on Twitter, Beatles drummer Starr, 75, said: "God bless George Martin peace and love to Judy and his family love Ringo and Barbara George will be missed."In a career spanning five decades, Sir George, who was 90, signed the Beatles and produced more than 700 records.
He worked with artists including Gerry and the Pacemakers, Shirley Bassey and Cilla Black.
He added: "Thank you for all your love and kindness George peace and love."
A carpenter's son from Holloway in north London, Sir George helped the Beatles achieve global success as the head of the Parlophone record label after hearing their demo tape in 1962.
He took them from their mop-top recordings in the early 1960s to the psychedelia of Sergeant Pepper.
In his lifetime, he won multiple Grammy awards and an Academy Award for the score to A Hard Day's Night.
In 1999, he was inducted into the Rock and Roll Hall of Fame.
Sean Ono Lennon, son of Beatle John Lennon, tweeted: "RIP George Martin. I'm so gutted I don't have many words."
Liam Gallagher, lead singer of rock band Oasis who modelled themselves on the Beatles, said on Twitter: "Sir George Martin RIP LG X