HSBC boss Antonio Simoes has publicly criticised gay City bosses who refuse to publicly disclose their sexuality.
Simoes was speaking at the LGBTI Out on the Street Europe Summit, which was hosted by Deutsche Bank, when he unleashed his criticism.
The HSBC UK chief executive, who came out as gay in a video message to his employees last year, said that City leaders were not taking advantage of all the good work that campaigners have done for gay rights.
"We're in London, we're in 2014," he said. "It's not acceptable that we take for granted all the work done by others on issues such as marriage equality."
Simeos said that being open about his sexuality has helped him to become a better leader as he believes that it makes him "authentic".
"I am the short, bald, Portuguese, gay guy. I have started to use it as a positive element of my personality," before adding that it enables him to be a "more empathetic and better leader".
His comments come shortly after Apple chief executive Tim Cook publicly acknowledged his sexuality for the first time, and Simeos said that Cook was "proud to be gay, and I consider being gay among the greatest gifts God has given me".