A Greenpeace campaign to protect the Sargasso Sea has garnered celebrity backing with the release of a music video filmed on the waters off Bermuda.

Dan Smith, the lead singer of the UK rock group Bastille, delivered a live performance of a previously unreleased song recorded on board the charity’s ship Arctic Sunrise.

Mr Smith, who wrote previous Bastille hits Pompeii and Happier, went on board the vessel while it was in Bermuda last month and joined the crew as it carried out research near the island.

He said the song, Blue Sky & The Painter, was inspired by artist Edvard Munch “finally seeing a crack of light in life after a period of darkness”.

“It felt like a theme that resonated with this particular opportunity that we now have to protect these vast blue spaces that we all depend on,” he said.

“I was invited on to this iconic ship to learn and help out, but when we found ourselves in unusually calm water within the Bermuda Triangle, 240 nautical miles [276 miles] away from the nearest land, it just felt like an ideal opportunity to collaborate with the crew on capturing this song.”

The video shows Dan Smith sitting on the prow of the iconic Greenpeace ship playing an acoustic guitar as the sun sinks into the deep blue water of ocean around him.

Mr Smith spent three days on board the Arctic Sunrise and also joined Keep Bermuda Beautiful volunteers in a clean-up on Cooper’s Island as part of the Oceans are Life campaign to urge governments to ratify the Global Ocean Treaty.

The treaty would help to ensure that 30 per cent of the world’s oceans are protected through a network of sanctuaries.

“Like so many of us, I’m really worried about climate change and massively keen to know how I can be useful,” he said.

“It’s been so interesting to learn that the oceans are one of our best defences against climate change and I wanted to bring people along on this amazing adventure that I’ve been lucky enough to be part of.”

Fiona Nicholls, an oceans campaigner at Greenpeace UK, said: “Dan performed this song of hope and resilience amid the bright blue waters of the Sargasso Sea, waters that are being heated by a changing climate and depleted by industrial fishing.

“His performance sums up our optimism that protecting our blue planet is possible with the help of the Global Ocean Treaty.

“This historic agreement was years in the making. Governments now need to sign it into their national law to kick-start ocean protection on a global scale.

“As the song goes … it's about damn time.”