Marks & Spencer is parting company with chairman Luc Vandevelde after he said he could no longer devote enough time to the business.

The M&S board is understood to have taken action after senior directors and big investors demanded that Vandevelde give the company more attention in return for his £450,000 a year and free suite at Claridge's.

Vandevelde reportedly said he could not do so and agreed to go.

Vandevelde was brought in four years ago to turn the ailing retailer round. But after some early successes, the retailer's results have failed to achieve lasting improvement. Although food sales have stabilised, the company's troubled clothing business has continued to struggle.

M&S confirmed that a search for a new chairman is underway and said Vandevelde would remain in post "for as long as necessary to establish his successor".