The tuna fish sandwich will disappear from the shelves of a high street food outlet because the chain’s boss was horrified by a film outlining the dangers of intensive fishing methods.

Pret A Manger’s co-founder Julian Metcalfe has removed tuna and cucumber sandwiches from the 190 Pret stores across the UK.

The entrepreneur, who launched the sandwich chain 23 years ago, is making the protest after seeing the hard-hitting environmental documentary The End of the Line. Inspired by a book written by the journalist Charles Clover, the film charts the plight of the bluefin tuna and describes how modern fishing is destroying the oceans’ ecosystems.

Metcalfe told the film’s producers: “Much as a result of your film, we took tuna out of Pret sushi entirely. No tuna in the box at all . . . so more in the sea, where they belong.”

He added: “We no longer sell the tuna and cucumber sandwiches at Pret. We do sell the Alaskan salmon, which is sustainable.”

Pret prides itself on an enlightened image. The chain actively helps homeless charities by distributing unsold food to the needy, supports social centres for underprivileged youth and concentrates

on selling sustainable ingredients.

Sales of bluefin tuna, a fish which conservationists claim is now as endangered as the panda and the tiger, have landed celebrity restaurant Nobu in trouble with its upmarket clientele.

The campaign against the London restaurant’s refusal to remove the endangered species from its menu has attracted widespread celebrity support. Greta Scacchi, star of White Mischief, is one of several stars who have posed naked with fish. She said: “I had my photograph taken with a dead cod. The point I was making is that it came from sustainable stocks.”

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