Ben & Jerry’s co-founder Jerry Greenfield was one of thousands of festivalgoers taking advantage of the free ice cream when his company’s Sundae on the Common hit Clapham last weekend.

This year’s headliners, Ash and the Charlatans, ensured the music festival again sold out within a couple of days, and with the company’s well-known green credentials, Mr Greenfield said the day would not only be enjoyable, but socially responsible.

The company’s ice creams – which now come in 20 flavours – are "climate neutral from cow to cone", and proceeds from ticket sales will also support the first wind energy project in Madagascar, said Mr Greenfield.

"I came to Clapham two years ago. It was great," he said. "We started the festival idea in the US as a small thank you to our customers. We had frog jumping contests and an ice cream eating competition.

"It was an extraordinary coming together, music, ice cream and being active on environmental issues. We thought it was the greatest thing. It was very powerful."