High street "Knicker Queen" Janie Schaffer is suing Marks and Spencer for a reported £1m after she left her job as lingerie and beauty director after just three months.

Schaffer was hired in January to transform M&S lingerie's frumpy image into sexy, sleek, and elegant bestsellers.

At the time of her appointment, M&S CEO Marc Bolland boasted of her "stellar retail pedigree" and claimed that she was a pivotal part of their brand revamp.

But within months of replacing Frances Russell - who was promoted to director of womenswear in November 2012 - Schaffer had resigned.

It was suggested that Schaffer walked out in a dispute over her job description, which she believed would give her full control over the lingerie business unit as well as responsibility for expansion through standalone lingerie and beauty shops.

According to the Financial Times, the 51-year-old designer, who co-founded lingerie chain Knickerbox in 1986, was seeking damages for the shares she claimed she lost out on at Victoria's Secret because M&S pressured her into starting as soon as possible.

She is also suing for the remainder of her years' salary.Schaffer was believed to have signed a two-year contract with M&S.

An M&S spokesperson said: "This matter is in the hands of our lawyers and we have absolutely no further comment to make."