Sadiq Khan said he understood the anger Amir Khan felt towards him after the sportsman’s £70,000 watch was stolen in east London.
The former world boxing champion, 35, said he and his wife Faryal were robbed at gunpoint by two men in Leyton earlier this week.
Khan has slammed the mayor of London for failing to tackle crime in the capital, urging him to ‘pull his finger off’.
Speaking at a St George’s Day event in Trafalgar Square, Sadiq Khan told PA news agency: ‘He’s in my thoughts, it must have been really scary for him.
“What’s really important is of course that if anyone knows who stole his watch from Amir Khan, they contact the police or contact Crimestoppers anonymously.
“It’s no consolation to Amir Khan that violent crime has declined in our city in recent years.”
He added: “I understand he was petrified, he was scared, it’s really important to understand and have empathy for victims of crime.
“As mayor, I regularly speak to victims of crime and it’s really painful when you’ve been robbed and I understand his anger, I understand his fear.”
The Metropolitan Police have asked the public for any information on the “easily” recognizable bespoke Franck Muller timepiece.
Officers were called just after 9pm Monday to High Road.
They said no shots were fired and no one was injured in the attack.
Khan, the former WBA and IBF light welterweight champion, told MailOnline: ‘My plan was to move to London later this year with Faryal and the kids but after what happened there is no there is no chance that we will.
London is no longer a place where I want to live.
“Our plan to move there is not happening.”
He also spoke of his anger over the incident.