Zara Phillips has signed a contract to be the face of Rolex watches.

The Queen's granddaughter and champion equestrian will receive pounds100,000 to appear in adverts for the Swiss watchmakers.

The first advert, which has appeared in US magazine Vanity Fair, shows the world eventing champion of 2006 posing with her horse Toytown who carried her to victory.

Zara, 26, will also receive three free watches from the company, including the pounds6,000 oyster perpetual featured on her wrist in the advert.

The young Royal was criticised Nike Shox Shoes two years ago for cashing in on her status by advertising Land Rovers.

Zara has also signed a deal with Virgin Books for her biography to be published next summer.

Marketing experts say she could earn up to pounds1 million a year through promotional contracts.