Bobby Womack diagnosed with colon cancer Bobby Womack (R) performs with Ronnie Wood of the Rolling Stones at the Rock and Roll Hall of Fam...

Bobby Womack diagnosed with colon cancer

Bobby Womack (R) performs with Ronnie Wood of the Rolling Stones at the Rock and Roll Hall of Fame 2009 induction ceremonies in Cleveland, Ohio April 4, 2009.REUTERS/Aaron Josefczyk

U.S. singer-songwriter Bobby Womack has been diagnosed with colon cancer, according to a message posted by his longtime friend Bootsy Collins on Facebook.

Funk bassist Collins said he had spoken to the soul musician over the weekend.

"He Wanted You All to Know That He Loves You & Thxs for the Prayers," Collins wrote. "Docs Says He Is In 1st Stage of Colon Cancer, He is Very Up Beat About His Future, we laughed & joked before we hung up."

Representatives for Womack could not immediately be reached for comment.

Womack, 68, was rushed to hospital in Houston, Texas earlier this month due to severe shortness of breath, and was scheduled to undergo "a minor heart procedure".

His best-known songs as a vocalist include "Woman's Gotta Have It" and "If You Think You're Lonely Now", and he also wrote hits for many other acts.

Womack's "It's All Over Now", which the Rolling Stones covered in 1964, gave the rock band its first British number one.

In 2010, Womack collaborated with British band Gorillaz on their album "Plastic Beach" and is due to release a new studio album "The Bravest Man in the Universe" in June.

He was inducted into the Rock and Roll Hall of Fame in 2009.