Sir Mick Jagger says working with his supergroup was “different” because they didn’t rehearse.

The Rolling Stones legend has formed SuperHeavy with Dave Stewart, Joss Stone, Damian Marley and A.R. Rahman. Their first release is reggae/pop song Miracle Worker and Mick has explained what it was like to work with the other artists.

“So it was very different because we didn’t know the people really well, we didn’t rehearse and we didn’t have songs written,” he laughed. “We just sort of sat there, looked at each other and started playing.”

Joss says Miracle Worker is her favourite track. She liked how easily it came together and thinks the end result is outstanding.

“That’s why I love that one because it was just a jam and we just kind of made it up as we went along and the lyrics sometimes went with the melody at the same time,” she told ET.

The rest of the band are just as enthusiastic about the single.

Dave was surprised with how well the group “gelled” as he’d been concerned their different backgrounds would prove problematic.

Dave was in Eurythmics, Damian is a reggae star, Joss sings soul music while A.R. is an Indian musician and producer.

“As soon as we started playing together in the studio, it gelled. All these different styles didn’t seem to be a problem to make them fit together,” Dave marvelled.

SuperHeavy’s eponymous album will hit stores on September 20.