diner had his luxury watch snatched off his wrist outside a high-end Mayfair restaurant.
The victim was targeted by a thief who tried to join his group of friends in Berkeley Square at 7.30pm on Tuesday.
CCTV shows the moment the suspect, disguised in a bucket hat, bends down and rips the watch off his wrist.
The video was said to show the man outside the prestigious sushi restaurant Sexy Fish.
The robber flees on foot with the victim close behind chasing him down the square.
A Scotland Yard spokesman said: “Officers attended and spoke to a man who said he was with a group of friends when another man walked towards them and integrated himself into their group as they crossed the road.
“He then approached the victim and managed to take his watch off his arm before fleeing the scene on foot.
“Officers carried out a search of the area but no trace of the suspect was found.”
Anyone with information should call 101 with reference 7122/30AUG22.