Charlize Theron, Sting and Trudie Styler, Woody Harrelson and Sienna Miller have also signed the letter to the Michelin-starred Japanese fusion restaurant, which is part-owned by Hollywood star Robert De Niro. In it they to say they can no longer "dine with a clear conscience" while Nobu continues to include the fish, recognised to be as endangered as the panda and white rhino, on its menu.
While acknowledging the restaurant – which has 24 branches and is a favourite haunt of stars – as one with "a fantastic reputation and enormous influence", the signees ask for bluefin tuna to "be completely removed from the menu due to its perilous position as an extremely endangered animal".
"The possibility that the magnificent bluefin tuna, one of the fastest creatures on the planet, could be extinct in as little as four years is a tragedy," they write.
Their gesture comes after Nobu's new policy of adding a warning to the menu about the fish's threatened status featured in a new film about the destruction of the world's fish stocks, entitled End Of The Line. The film reveals how the bluefin, which used to be abundant in the Mediterranean and the Atlantic, has been fished to the point of extinction.
Unimpressed by Nobu's amendment, celebs are adamant it must be removed altogether.
Writing on his Twitter page, Stephen Fry said: "It's astounding lunacy to serve up endangered species for sushi. There's no justification for peddling extinction, yet that is exactly what Nobu is doing in restaurants around the world."