Pink Floyd keyboard player and founder member Richard Wright has died, aged 65, from cancer.
Gilmour said: "No-one can replace Richard Wright - he was my musical partner and my friend."
Writing on his website, he added: "In the welter of arguments about who or what was Pink Floyd, Rick's enormous input was frequently forgotten."
Pink Floyd achieved legendary status with albums including 1973's The Dark Side Of The Moon, which stayed in the US album chart for more than a decade.
Wright wrote The Great Gig In The Sky and Us And Them from the album.
Wright's spokesman said in a statement: "The family of Richard Wright, founder member of Pink Floyd, announce with great sadness that Richard died today after a short struggle with cancer.
A very tragic loss
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