The late Queen rocker and comedian Kenny Everett reportedly gave the British royal - who died in a car crash in Paris in 1997 - an army jacket, cap and sunglasses to wear for a night out in South London homosexual haunt the Royal Vauxhall Tavern in the 1980s, according to comedienne Cleo Rocos.
A piece in Cleo's new memoir 'The Power of Positive Drinking' - which is serialised in the Sunday Times newspaper - explains: ''Freddie told her we were going to the Royal Vauxhall Tavern, a notorious gay bar in London. Diana said she had never heard of it and said she'd like to come.
''Now this was not a good idea. 'It's not for you,' said Kenny, 'It's full of hairy gay men. Sometimes there are fights outside.' This didn't put her off in the slightest.''
Cleo claims the princess had a great time and wasn't recognised during the evening, despite the group's concerns, and was able to order drinks at the bar.
She wrote: ''When we walked in ... we felt she was obviously Princess Diana and would be discovered at any minute.
''But people seemed to blank her. She sort of disappeared but she loved it.
''She did look like a beautiful young man.''
Freddie died in 1991 aged 45 of complications caused by AIDS, while Kenny passed away in 1995 aged 50 from an AIDS-related illness.