LONDON - Almost 300 British arts and culture figures have appealed for voters to support European Union membership, arguing that a vote to leave the 28-nation bloc in a June 23 referendum will leave the U.K. "an outsider shouting from the wings."

Signatories to Friday's letter include "Sherlock" star Benedict Cumberbatch, actors Bill Nighy, Keira Knightley and Kristin Scott Thomas, spy novelist John Le Carre, "Wolf Hall" writer Hilary Mantel, fashion designer Vivienne Westwood and "Slumdog Millionaire" director Danny Boyle.

The letter says many creative projects "would never have happened without vital EU funding or by collaborating across borders." It argues that Britain's creative success "would be severely weakened by walking away."

Entertainers who support leaving the bloc include actor Michael Caine and singer Roger Daltrey of The Who.