The Barbican is staging an art exhibition so risque that it is for over-18s only. Seduced: Art And Sex From Antiquity To Now will feature representations of sex over the past 2,000 years.

Indian manuscripts, Baroque paintings, Roman marbles and 19th century photographs will be among the works on display.

There will also be a sound installation entitled The Voice Of Sex with readings from erotic texts, such as the Kama Sutra, Lolita and the writings of the Marquis de Sade.

The Barbican hopes the show will provoke debate about the boundaries between art and pornography.

"The exhibition highlights the relationship between viewer and artwork and provides the historical and cultural framework for us to question our own boundaries - where does art stop and pornography begin?" a spokeswoman said.

"Is an explicit painting from an ancient Pompeian brothel acceptable because it is hallowed by time, while its modern equivalent is not? Because something can claim 'aesthetic merit', can it be exempted from charges of obscenity?"

In ancient Greece, explicit images of heterosexual and homosexual sex were commonplace. Japanese prints also feature graphic depictions of sex. But British attitudes towards sex are rather more prudish.

Among the highlights of the exhibition is a half-metre high plaster cast fig leaf made to hide the private parts of Michelangelo's David in the presence of Queen Victoria.

A cast of the statue arrived in London in February 1857 as an uncalled-for diplomatic gift to the Queen from the Grand Duke of Tuscany.

Victoria was apparently so shocked by the nudity that a proportionally accurate fig leaf was hastily commissioned from London firm D Brucciani & Co. David is shown wearing the leaf in a photograph taken at the time. The exhibition opens on October 12.