For the past quarter of a century, a major painting by Francis Bacon has languished in a storeroom in Iran, its eroticism deemed too inflammatory for public display.
But now British art lovers are to get the chance to see the work which has been kept from Iranians. Tomorrow the extraordinary triptych Two figures lying on a bed goes on display after years of negotiations by the Tate.
The work is owned by the Tehran Museum of Contemporary Art, an institution originally founded by the wife of the last Shah of Iran and the holder of an extraordinary collection of Western paintings.
But it was one of dozens of depictions of nudes consigned to storage after the fundamentalists seized power in the 1979 revolution.
Like most younger Western academics, Stephen Deuchar, the director of Tate Britain, knew the work only through reproduction. So when he was on holiday in Iran in 2001, he naturally asked to take a look.
Even under the harsh fluorescent lighting of the underground store, it was striking. He asked whether he could borrow it. And the Iranian Ministry of Culture finally agreed.
Surveying the work on the walls of Tate Britain yesterday where it is the highlight of a new temporary Bacon display, he said that it was even more striking seen properly.
"When you saw it under the fluorescent lighting in the store, you could tell it was a strong work, but it looks very vibrant here. The lilac background is very surprising," he said.
Toby Treves, who has curated the display, said the work, which was painted in 1968 not long before it was sold to the Shah's wife, clearly showed a homoerotic strand of Bacon's work that was largely ignored.
"At the beginning of his fame after the war, there was a concentration on the existential aspect of the work, but not much discussion of the quite frank eroticism in many of the paintings," he said. "This triptych is probably the most overtly erotic of the paintings in this room."
The work shows figures in two flanking panels who appear to spy on two naked men lying on a bed in the central panel, with a splatter of white paint flung across them. "It is deeply ambiguous and deliberately so," Mr Treves said.
The Iranian loan is hung alongside another celebrated triptych, his Three Studies for Figures at the Base of the Crucifixion, dating from 1944, and a work apparently based on photographs of the former cricketer David Gower. Bacon triptychs now command as much as £6m at auction.
The generosity of the Iranian museum and its director, Dr Ali Reza Sami Azar, was returned earlier this year when the Tate lent a Bill Woodrow to an exhibition of British sculpture organised by the British Council.
And extraordinarily, it now looks as if the Bacon may even be seen in Tehran itself. Dr Sami Azar is hoping to include Two figures lying on a bed in an exhibition provisionally entitled Figurative Tendencies in Western Art when it is returned to Iran in the autumn.