The collection was snatched from the bike as it was returned to de Grisogono's shop in New Bond Street, central London.

Investigators believe the parcel was taken as the courier stopped at a petrol station as he travelled to the West End.

The package included distinctive white pendant earrings encrusted with diamonds, a coral and diamond ring, and a gold bracelet.

Walsh, 27, wore the jewellery at the Cosmopolitan Ultimate Women of the Year Awards last week where she was named Ultimate Woman's Woman.

A Metropolitan Police spokesman declined to discuss the value of the stolen jewellery.

He said: "We can confirm officers from Barnet CID are investigating the theft of two parcels.

"They went missing whilst in transit from properties in north London to properties in central London.

"One parcel contained a quantity of jewellery, the other some paperwork. They belong to two different parties.

"The theft was reported to us on Thursday November 12. Inquiries
continue. No one has been arrested."

The manager of the de Grisogono store in New Bond Street, who declined to give her name, said: "We have no comment on that whatsoever."