Nothing has been announced, but the 54-year-old British singer, who is touring the Middle East, says: "There's a possibility. I'm open for it."
"If it doesn't happen, it won't be because we don't want to. It will just be because there are too many things in the way," he said Sunday. "I'm happy to sit behind the drum kit and let Peter (Gabriel (search)) be the singer, but if it happens, I'll be there."
Genesis formed in 1967, performing for more than 30 years before disbanding in 1998. Collins fronted the band after lead singer Gabriel left in 1975 to pursue a solo career.
Collins went solo in 1996.
"We're all still good friends. We spent like 30 or 25 years of our life in the same office," Collins said. "Just because we don't play in the same band anymore doesn't mean we don't see each other and enjoy each other's company."