London: A string of British stars, among them actors Benedict Cumberbatch, Keira Knightley and Jude Law, has signed a letter that withdrawal of Britain from the European Union (EU) would "damage" the creative industry. Almost 300 actors, musicians, writers and artistes are opposing Brexit -- Britain Exit movement -- and backing calls for Britain to stay on in the EU. They say "vital EU (European Union) funding" and work across borders has been key to projects from galleries to blockbusters, the BBC reported. But "House of Cards" author Lord Dobbs said British success in the industry was "not because of the EU". The letter, organised by the Britain Stronger in Europe campaign, says: "Britain is not just stronger in Europe, it is more imaginative and more creative, and our global creative success would be severely weakened by walking away. "Leaving Europe would be a leap into the unknown for millions of people across Britain who work in the creative industries, and for the millions more at home and abroad who benefit from the growth and vibrancy of Britain's cultural sector." Other famous names to sign the letter include Juliet Stephenson, Derek Jacobi, Helena Bonham Carter, Bill Nighy, Dame Kristen Scott-Thomas, Mike Leigh, Sophie Okonedo, John Hurt, Steve McQueen, Kelly Hoppen, Eddie Izzard, Sandi Toksvig, Jarvis Cocker, Oona King, Danny Boyle and Hilary Mantel.