Saatchi's new sensation: the Peeing Madonna

Charles Saatchi, the art collector who has exhibited works such as Tracey Emin's unmade bed and Damien Hirst's pickled shark, is to display one of his most outrageous works yet.

As the centrepiece of a new display of recent acquisitions he will unveil a sculpture in which more than a dozen religious icons of Jesus Christ and the Virgin Mary have been fitted with penises and gathered around a urinal.

The "offensive" artwork, Medusa by Terence Koh, will show at "USA Today", a new exhibition of young American artists due to open at the Royal Academy of Arts next month.

Mr Saatchi ranks Koh as one of the most gifted sculptors in the US, and many of Koh's works feature his own blood and semen.

Mr Saatchi said: "Terence Koh's work is as nasty as you like. He has the face of an angel but the soul of a sewer rat. He and Banks Violette are the two most exciting new sculptors in America." Violette is another artist featured in the month-long exhibition.

Chinese-born Koh, 29, lists his own urine as one of the components in Medusa, a steel urinal inside a water closet which also contains a shelf crowded with the religious figures, each with a crudely fashioned phallus.

This exhibition comes almost 10 years after Mr Saatchi's Royal Academy exhibition "Sensation" caused widespread outrage, featuring massive images of the child murderer Myra Hindley by Marcus Harvey as well as Chris Ofili's depiction of the Virgin Mary, which contained pornographic magazine images.

Nathan Paine Davey, secretary-general of the Society of Mary, which is devoted to honouring the Virgin, said: "If the artist has attached phalluses, I think most people would find that grossly offensive."