Mayor of London Boris Johnson kicked off this year’s London Gay Pride festival, marching under the banner of the Gay Liberation Front.

Marching alongside Mr Johnson were equality minister Lynne Featherstone and Tory MPs Nick Herbert and Margot James, who is openly lesbian.

Peter Tatchell was present, carrying a banner emblazoned with the words, “David and Sam Cameron can Marry – Gays Can’t. End the Ban on Gay Marriage”. In resoponse to this, Mr Johnson said: “If we can have a coalition between Tories and Lib Dems, why can’t we have gay marriage?”

Mr Tatchell responded: “There you are – the mayor supports gay marriage”.

With warm and sunny weather forecast for the rest of the day, the parade is expected to attract up to a million people.