Brad Pitt has made an appearance at a charity concert amidst his ongoing custody battle with Angelina Jolie.

Chris Cornell, Sting, and Brad Pitt

Chris Cornell, Sting, and Brad Pitt

The 53-year-old actor has been laying low since his estranged wife filed for divorce last year and entered into a bitter legal feud over the custody of their six children - Maddox, 15, Pax, 13, Zahara, 11, Shiloh, 10, and eight-year-old twins Knox and Vivienne - but stepped out at the Rock4EB! concert in Malibu, California, to raise money for the Epidermolysis Bullosa Medical Research Foundation.

The 'Fury' star was joined at the star-studded event by the likes of Soundgarden frontman Chris Cornell, Sting, Zach Galifianakis and Courtney Cox.

Chris, 52, took to his Instagram account to share a picture of himself with the Hollywood star and the former Police frontman, which was captioned: "Had an amazing night performing for #Rock4EB with @theofficialsting & #bradpitt (sic)"

And in a video posted on the photo sharing website by an onlooker, the 'Allied' actor was seen taking to the stage to introduce the 'Black Hole Sun' hitmaker.

He said: "I get to introduce a very, very good friend of mine. Someone I've known for quite a while, and am a huge fan of ... Chris Cornell.

"Thank you so much for having me out here tonight, this is so much fun I really appreciate it."

For Brad, the outing comes after he made a surprise appearance at the Golden Globe awards earlier this month to present an introduction package for Best Motion Picture - Drama nominee - and eventual winner - 'Moonlight', which was produced by his own company Plan B.

The actor said of the Barry Jenkins-directed film: "It's born of the courage of a group of actors willing to strip to their souls and express their humanism inside mistake and misstep and misdeed.

"It is Barry Jenkins profound belief that we all stand at the threshold of change and forgiveness where we only grant acceptance and love to ourselves."