Moss, who has just turned 33, is understood to have been axed after it was reported that the Coty-owned brand has been holding secret castings for younger models to replace her. Moss has starred in ads for the brand for more than five years.
According to a report in the News of the World, Moss is understood not to have been told as yet, but an official announcement is expected shortly. Rimmel's creative account is handled by JWT.
A source told the paper: "Age catches up with everyone -- even Kate. But she hasn't been told anything by Rimmel. At 33, she's getting on in terms of modelling. And she recently moaned about her face, saying she needed Botox.
"Rimmel is a range for the younger market so that worried them. Now bosses are looking for younger models who can give the brand a fresh approach. Girls have been contacted in secret."
Rimmel was under pressure to dump Moss in September 2005 when the Daily Mirror broke a story with pictures of the model snorting cocaine. US drugstore giant Walgreens was one retailer that called on Rimmel to drop the model as other fashion houses did at the time, including H&M, Chanel and Burberry.
However, Rimmel stuck by her as did a number of other brands and she went on to sign new lucrative deals including ones with Virgin Mobile, Stella McCartney, lingerie maker Agent Provocateur and a return as the face of Calvin Klein for around £500,000 in April. She is understood to be worth more than £30m.
In 2001, when Moss first appeared in a Rimmel campaign, it marked a new direction for the brand. It was the first time that Rimmel had worked with one lead face. The television, press and poster campaigns that have featured Moss have positioned the brand as edgy, street-wise and cool while reinforcing its London heritage.
They have variously shown Moss out on the town, fixing her make-up in black cabs as she goes from one glamour spot to another.
Moss, who is dating Babyshambles singer Pete Doherty, is also reported to be in talks with cosmetics firms to launch her own make-up range.
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