The BBC\'s director-general Mark Thompson has been named as the chairman of BBC Worldwide, the corporation\'s £1bn-a-year commercial arm responsible for merchandising and overseas sales of programmes. Mr Thompson\'s surprise appointment, in addition to his duties as director-general, means the BBC will not have to conduct an external search for the job. The Independent revealed last week that the corporation had begun a formal search to find a replacement for Robert Webb, who stepped down last month. It will also save on the £77,000-a-year salary paid to Mr Webb, the former British Airways legal counsel who has taken the same position at Rolls-Royce. BBC Worldwide generates a crucial income from commercial sales from hit shows such as Dr Who (pictured) and Planet Earth, which supplements the £3.6bn from the licence fee. Mr Thompson is likely to remain as chairman of Worldwide for only a short time as BBC Trust chairman Lord Patten has hired recruitment firm Egon Zehnder to find his successor as director-general.