Minnelli released a statement revealing she has considered Hamlisch, who worked with her mother Judy Garland, a "best friend" since she was 13.
She adds, "He arranged my first album, my second album, the songs for Judy Garland & Liza Minnelli at the London Palladium and just about everything else.
"He was one of the funniest people I knew. I will miss his talent, our laughter & friendship, but mostly I will miss Marvin... I have lost my first lifelong best friend, and sadly we have lost a splendid, splendid talent."