The direct selling cosmetics firm said it had hired Outhwaite, who played Melanie Owen in the BBC soap, but would not confirm stories that she would appear in television ads for the company or that the deal was worth 拢250,000.
Avon advertises on television in the US, but it has not yet undertaken a TV campaign in the UK.
The company retains Carat as its media agency, but has no advertising agency and refused to comment on whether it has plans to hire a creative agency. Its UK print advertising is currently done in-house.
Earlier this year, Avon signed the band Atomic Kitten as the face of its teen brand Color Trend for a year-long contract.
Outhwaite, whose mother was reportedly once an Avon lady, told the Sunday Mirror: "I'm happy the cat's out of the bag. But you'll have to wait until next year to catch me in action. And I might be knocking on a door near you!"
Outhwaite will next be seen on screen in October in the BBC drama series Red Cap, where she plays a member of the British Army's Special Investigation Branch of the Royal Military Police based in Germany.
In the UK, Avon has a 160,000-strong sales force. Last week, its New York-based parent company said it was launching a new brand called Mark, aimed at a younger audience than Avon's traditional products.
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