Lady Gaga, seen performing at the Brit Awards on Tuesday, is invited to participate in Spencer Tunick's upcoming massive nude installation and photo shoot in Sydney. (Andy Paradise/Associated Press) The deadline is quickly approaching for Spencer Tunick's upcoming shoot at the Sydney Opera House, but the U.S. photographer famed for his massive nude installations has nonetheless extended a last-minute invitation to a famous figure: dance-pop star Lady Gaga.

Tunick is making final preparations to travel to Sydney for the shoot on the steps of and inside the famed venue. Still, he told Australian media this week he would love for the Grammy Award-winner and music world chart-topper to join in.

"I would like to send an open invitation to Lady Gaga to fly to Australia and participate in my next installation in Sydney at the Opera House on March 1," Tunick said.

The New York-based photographer, whose installations have nude volunteers posed against rough urban and natural landscapes, said he would be open to however the outrageous and theatrical performer might want to appear.

"I was thinking she could slip in there anonymously and no one would know she was there. I'd be glad to not tell a soul," he said. "Or maybe she would want to pose. Maybe she would want people to know she was there but just couldn't be found in the crowd. You know, then it could be like 'Where's Lady Gaga?' "

However, he reiterated that all of his installation volunteers, famous or not, appear in the buff — no exceptions.

Tunick says Lady Gaga would be welcome at his upcoming shoot, but reiterated that she would have to be nude like all the other volunteer subjects. (Dario Lopez-Mills/Associated Press)Lady Gaga, who picked up a trio of trophies at the Brit Awards this week and a pair at the Grammy Awards on Jan. 31, revealed recently that she considered Tunick an inspiration and had penned a thesis on his work when she was younger.

Tunick's upcoming Sydney shoot, entitled The Base, will coincide with the city's annual gay and lesbian Mardi Gras festivities and will feature straight and gay or lesbian volunteers.

Michael Rolik, the chief executive of the Sydney Mardi Gras, told Australian media the U.S. singer would be welcomed if she chose to participate.

"Lady Gaga is a powerhouse figure in the world of performance art and a strong supporter of gay and lesbian community worldwide," he said.

Tunick has shot his nude installations around the globe, including in Mexico City's massive central Plaza de la Constitucion, inside New York's Grand Central Station, outside Montreal's Museum of Contemporary Art and on the Aletsch Glacier in Switzerland.