Luca said that in June an officer suggested he should drop the case because, if it went to court, the suspect would learn his identity and could therefore endanger his life due to “potential retaliation”.
He says he was also told that if he pursued the case, the suspect would likely receive only “a few hours of community service” as a court sentence.
Luca said there had been a “complete failure of the system” to catch those responsible for the crime, adding the Met Police could “do better”.
The finance professional said the theft took place in the restaurant’s “outdoor terrace” on Elystan Place at about 19:30 BST.
“Three people approached me,” he said. “In one millisecond the watch was gone.”