Firewind's long-term vocalist, Apollo Papathanasiohas, has quit ahead of the Greek metal band's imminent US tour.

Even though Papathanasio had been temporarily replaced for touring duties a few times, he appeared on all Firewind releases since 2006’s Allegiance, and the band’s upcoming live album will feature recordings from his recent final shows with the group.

In a statement, the band said: "For the past few years it was evident that Apollo could not keep up with Firewind’s ever growing and demanding touring and promotional schedule. Several times we've had to recruit replacements in order to continue touring the world and keep playing for our fans."

Papathanasio dropped out of a European tour in 2011, which guitarist Gus G (pictured) discussed in an interview with Music-News. He said: "It doesn't even surprise me anymore. Our motto is ‘the show must go on’ and that's what we always do."

The band have announced Kelly Sundown Carpenter (Adagio, Beyond Twilight) as their new singer. They head to North America in February for a month-long tour with Turisas and Stolen Babies, and return to the UK in August for the Bloodstock festival in Derbyshire.

Firewind ended 2012 by playing four club shows in Greece to mark their 10th anniversary. They also headed into the studio to mix recordings from latest album Few Against Many for an upcoming live record due for release this year.