AceShowbiz - PETA bosses have urged Coldplay to only serve vegan food on their upcoming "Music of the Spheres" World Tour.

Chris Martin and the band will embark on a global stadium tour in 2022 in support of their ninth studio album, which they promise will be the most eco-friendly shows they've ever performed.

And in an open letter addressed to the "My Universe" hitmakers, PETA (People for the Ethical Treatment of Animals) has suggested the band could further reduce their carbon footprint by opting to only have plant-based food at the venues they play.

PETA's Director Elisa Allen wrote, "As you may know, animal agriculture contributes to many of the serious environmental problems the planet is facing."

"It's little wonder, then, that the United Nations states that a transition to vegan eating is urgently needed to prevent the worst effects of the climate crisis. And this can be as simple as swapping beef burgers for bean burgers."

"We hope you'll agree that cutting damaging animal-derived foods from concert venues is a no-brainer."

The upcoming shows will be powered by 100 per cent renewable energy, and there will be rewards on offer for fans who travel to the gigs via public transport.

The "Clocks" hitmakers are also donating 10 per cent of ticket sales to climate change charities, while for every ticket sold a tree will be planted.

The Grammy-winners have also teamed up with direct air capture pioneers, Climeworks, to help ensure their 'Music of the Spheres World Tour' will have, at minimum, a net-zero carbon footprint.

They said in a statement, "Playing live and finding connection with people is ultimately why we exist as a band. We've been planning this tour for years, and we're super excited to play songs from across our whole time together."

"At the same time, we're very conscious that the planet is facing a climate crisis."

"So we've spent the last two years consulting with environmental experts to make this tour as sustainable as possible, and, just as importantly, to harness the tour's potential to push things forward."

"We won't get everything right, but we're committed to doing everything we can and sharing what we learn. It's a work in progress and we're really grateful for the help we've had so far."