Petra Ecclestone, the daughter of F1 billionaire Bernie Ecclestone, has had £500,000 worth of jewellery stolen from her London mansion after the property was viewed by a thief posing as a 'Kazakh millionaire'.

According to the Daily Mail, the 24-year-old socialite, who recently put the £32 million home in London's Belgravia up for sale, was targeted during a 'fake' viewing.

Diamond earrings and a diamond Rolex watch are said to have been stolen from the property. She was not present at the time of the robbery.

"Petra thought that anyone going to see her home would be thoroughly vetted," a friend told the Daily Mail.

"She was out with her sister Tamara a few weeks ago when the viewing took place. As soon as this man left, it was discovered that the jewellery, which was on a bedroom nightstand, was missing."

Ecclestone's main home is in Los Angeles, where she lives in a £55million ($85million) estate. The mother-of-one, however, has been staying in London for the summer with her husband James Stunt and baby daughter Lavinia.

Her older sister Tamara's house in Chelsea, West London is also up for sale after she moved into a new home with her husband Jay Rutland.

The source says that Ecclestone believed her home was targeted because it was still furnished.

The stunning six-storey property features its own cinema, an iconic picture of Raquel Welch on a cross, Damien Hirst artwork, and its own private gym.

The alleged thief, who is said to have viewed several other multi-million dollar properties in the area in the past two months, is said to have called himself Oleg. He allegedly arrived in a chauffer-driven Bentley and he never removed his sunglasses.

"It did seem very odd. There are only a certain number of these kind of exclusive properties for sale - he never asked to see Tamara's house because it was unfurnished and unlived in."

"This man was left to walk around the house on his own and the estate agent is not cooperating with the family."

Ecclestone is apparently not intending to claim for the theft on insurance and the robbery was not reported to police.

"The theft occurred at the London house during a property viewing. the family were not home at the time. no further comment will be made," he spokeswoman said.