The licensing expert will not renew his contract, claiming that City Hall failed to give the body the independence it required.
In a letter seen by The Evening Standard, Kolvin, who was appointed to the position by the London mayor Sadiq Khan in December 2016, says City Hall hasn't given the Night Time Commission the independence, nor the publicity or administrative support, to achieve its aims. "I regret that I cannot allow my professional independence to be compromised," he wrote. "Nor can I serve on a commission which lacks independence."
"I have also offered my services for free to take the project forward, if only these issues can be resolved," he continued. "Sadly, they have not. In these circumstances, I have no option but to permit my contract to expire."
Originally launched by the former mayor Boris Johnson in 2016, the commission was revamped under Khan as part of City Hall's bid to turn London into a 24-hour city. Despite Kolvin's departure, "the important work of the commission will continue and a new chair will be appointed in due course," said City Hall.