According to the Sunday Times, chairman Chris Powell, the brother of Tony Blair's chief of staff, Jonathan, has asked for the creative team to come up with a pro-euro slogan that can run on everything from posters and TV to public platforms and campaign literature.
The email from Powell to BMP staff tells creatives to play on public fears about Britain remaining outside the euro, according to the Sunday Times, but must not sound defeatist. The email also says that the word "isolated" is a powerful weapon.
"What we need: A campaign line for the pro-euro campaign. It will appear on everything: behind Blair and Brown when speaking (so has to work small on TV) and on all literature. The sentiment: People know the world is coalescing into groups. It is counter-intuitive for Britain to be off on its own," the email says.
It is unclear from the emails if the agency has been officially appointed or if Labour is simply falling back on old relationships with the agency. BMP has run four Labour election campaigns before standing down prior to the 1997 campaign, which was handled by Trevor Beattie and TBWA\.
The newspaper suggested that the government could be using the agency to develop ideas for a pro-euro roadshow, which ministers will use to convince the public that euro entry is right for Britain ahead of a referendum campaign.
No date has been set for a euro referendum and most believe it is unlikely to come until Labour has secured a third term in office.
Powell said that while the emails were authentic he said the agency had not been "specifically" tasked with coming up with a pro-euro advertising slogan.
He also said it has no standing. However, this is put into doubt by a second email from the agency's joint deputy creative services director, David Holmes, sent to agency staff.
"For all the frustrated copywriters amongst you that want to see their work all over News at Ten/the national press and secure their name in the... advertising hall of fame, please see below," the email said.
The report said that at least one slogan, "A no vote leaves us nowhere" has already been rejected, because nobody has yet been asked to vote yet.
A Downing Street spokesman refused to comment on leaked documents.
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