Tesco is preparing to start the search for a new chairman to replace David Reid.

The UK’s biggest retailer is reported to have appointed headhunters to find a replacement for Reid, who has been chairman since 2004 and on the company’s board since 1985.

Senior independent director Patrick Cescau is leading the search, but is understood not to be a candidate for the role.

Reid is not expected to stand down until 2012, alowing him plenty of time to oversee the transition to new chief executive Philip Clarke, who takes over from Sir Terry Leahy next March.