British celebrities band together in support of pro-EU campaign

If Britain chooses the leave the European Union (EU) this June, the country is at risk of becoming "an outsider shouting from the wings", stars from the creative industries have warned.

Over 280 actors, musicians, novelists, designers, artists and directors have signed an open letter, showing their support for Britain to stay in the European bloc, just weeks before the final vote.

Benedict Cumberbatch | Keira Knightley | Patrick Stewart
Getty Images: Mike Marsland/WireImage | Alberto E. Rodriguez/Getty Images | Allen Berezovsky/WireImage

Actors, Benedict Cumberbatch, Patrick Stewart, Keira Knightley and Jude Law are among those who've signed the pro-EU letter, with other prominent figures including Danny Boyle, Vivienne Westwood, Eddie Izzard, Helena Bonham Carter and Bill Nighy.

In the letter, received by CNBC, the stars argued that the EU had provided "vital" funding and collaboration to U.K. projects, and an exit would mean a "leap into the unknown" for millions who work and benefit from the creative industry.

"From the smallest gallery to the biggest blockbuster, many of us have worked on projects that would never have happened without vital EU funding or by collaborating across borders," the letter reads.

"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."

"We believe that being part of the EU bolsters Britain's leading role on the world stage," the letter added.

Britain in the EU? UK's industries have their say

The letter comes as the Creative Industries Federation released its latest survey findings on Friday, which revealed that over 96 percent of the federation's members would back staying in the EU.

In the survey, reasons given as to why the U.K. would be better in the EU, included access to EU funding, markets and influence; the federation claimed the European bloc is the "largest export market for the UK creative industries".

"The UK creative industries are key to the way we are seen by the world and deliver a massive £84.1 billion ($122.3 billion) to our economy. Our position as a vital European creative hub is a huge part of this success," Sir John Sorrell, Creative Industries Federation chairman, said in a statement.

Aside from Sorrell, Penguin Random House UK's chair, Universal Music UK's CEO and chairman, and Working Title Films' co-chairmen all signed the letter.

Brexit debate rhetoric gets extreme as vote nears

There are those however, who have come out in favor of leaving the EU, including Sir Michael Caine, former footballer Sol Campbell, and The Who frontman Roger Daltrey.

British citizens will head to the polls on June 23, to decide whether their country's future is better with or without the political-economic bloc.

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