TOPSHOP, the high-street fashion chain owned by Sir Philip Green, is losing one of its top executives after more than 19 years. Karyn Fenn, joint managing director, is preparing to quit the company and her resignation is expected to be announced early this week.

Fenn’s departure comes after Jane Shepherdson – described as the most important woman in fashion by Drapers, the fashion business journal – resigned from Topshop last October.

Both women have left the business since Green opted to take a much more hands-on role at his flagship retailer. It is understood that Fenn will not be replaced, and Mary Homer, the other joint managing director, will take sole day-to-day charge of the business alongside Green.

Homer and Fenn were promoted in December to run Topshop in the wake of Shepherdson’s departure.

Critics will inevitably seize on the news as a sign that cracks are appearing in Green’s fashion empire, but City sources said this weekend that the billionaire retail magnate was relaxed about Fenn’s departure and confident of the strength and depth of the Topshop management team.

The brand is the crown jewel in Green’s Arcadia group, which also includes Miss Selfridge, Burton and Dorothy Perkins. The news comes as Topshop is on track to deliver record profits of more than £100m this year.

The retailer is also in the middle of an ambitious expansion programme, under which it will open 400,000 sq ft of net new selling space during the next 18 months, increasing the existing 1.3m sq ft of trading space by more than a third.

Last week Topshop opened a new 32,000 sq ft store in Cardiff and it will open giant new stores in Liverpool, Edinburgh, and White City and Brent Cross in London.

The business has enjoyed a big boost from a new clothing range designed by supermodel Kate Moss which has led to bumper sales. A new, larger Moss range will be in stores this autumn.

Topshop is also taking its first steps to crack America. The Moss range is on sale in the Barneys department store chain in America and Green is searching for sites for a flagship Topshop store in Manhattan. He has indicated he will spend about $100m (£49m) opening three Topshop stores in the heart of New York if he can find suitable properties.

Over the coming three years Green plans to open more than 100 Topshop stores overseas.

Analysts believe that Green may eventually decide to float Topshop.

The news about Fenn’s departure comes just weeks after The Sunday Times revealed that Allan Leighton, the chairman of the Royal Mail, held secret talks to try to buy the BHS store chain from Green. The talks have since ended and Green is adamant that BHS is not for sale.

He is now searching for a new chief executive for BHS and is pressing ahead with an ambitious refurbishment programme. Ten BHS stores have been revamped in the past three months and ten more will be refurbished in the early autumn.

Green is one of the most successful entrepreneurs in the retail industry. Born in Croydon in 1952, he left school at 16 but got his first job at 12, working for a shoe importer. He made his first million in the 1970s by buying, turning round and then selling a jeans retailer called Jean Jeannie.

During the 1980s and 1990s the profits from his entrepreneurial schemes mushroomed. In 2002 he became the second-biggest force on the high street (after Marks & Spencer) when he paid £850m to assume control of the Arcadia group.

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