LONDON, England - Kate Bostock, the former boss of clothing at Marks & Spencer, has returned to Britain's stores sector as chief executive of Coast, the privately owned women's fashion chain said on Wednesday.

Bostock quit online fashion retailer ASOS in July after just seven months as executive director of product and trading, deciding the fast-growing online fashion firm that targets young women looking to emulate the designer looks of celebrities wasn't for her.

She previously spent eight years at Marks & Spencer, Britain's biggest clothing retailer, as head of general merchandise, making her one of the most powerful women in the retail sector.

Bostock, 56, has also worked for Next, Britain's second-largest clothing retailer, and for the George brand at Asda, a subsidiary of the world's largest retailer, Wal-Mart Stores Inc.

She will join Coast in September and will work closely with chairman Derek Lovelock and the senior management team, with a focus on broadening the brand's offer beyond mainly formal wear, as well as online development and international expansion.

The firm currently trades from 370 stores in 26 countries. International sales already contribute over 35 percent of the brand's turnover.

Her appointment comes after Coast's former parent, Aurora Fashions, partly owned by Icelandic bank Kaupthing, unveiled plans in March to make Coast a stand-alone business and combine its two other retailers, Oasis and Warehouse, into a new business.

Analysts said Bostock's appointment may lead to speculation that Coast plans to float in the future.