5,000 naked people embrace on steps of Sydney Opera House

It started off as an art project at Alleyn's School in Dulwich more than 20 years ago but has grown into a global phenomenon culminating in this latest audacious stunt.

About 5,200 naked people embraced each other on the steps of Sydney Opera House for a photo shoot by American artist Spencer Tunick to mark the city's gay and lesbian Mardi Gras celebrations.

Tunick instructed participants to adopt a number of poses, from standing up, lying down and even embracing cheek to cheek, as the sun rose over Sydney Harbour.

He said: "It was difficult to get the straight participants to embrace the gay participants and vice versa. So I was very happy that the last set-up finally got done and everyone came together (in a) united, friendly kiss, a loving kiss in front of this great structure."

Tunick has produced almost 100 installations around the world. He says his work is not about exhibitionism or eroticism but reveals the vulnerability of life in a rough city landscape.