Queen and Paul Rodgers have released the single "Say It's Not True" to mark World AIDS Day.

Queen has made the song available for free download to "help Nelson Mandela with his campaign" against AIDS, according to The Associated Press.

Freddie Mercury, Queen's famous lead vocalist, died of an AIDS-related illness in 1991.

"By making the song available for free, we hope to help Nelson Mandela with his campaign to get across the message that no one is safe from infection," drummer Roger Taylor said in a statement. "We have to be aware, we have to protect ourselves and those we love."

He said the song follows the line of Mandela's personal message: "It's in our own hands to bring a stop to this."

"Say It's Not True" is Queen's first studio collaboration with Rodgers.

You can download "Say It's Not True here for free.