Unshown Bacon portrait exported from Iran

For 25 years, it has languished in the vaults of the Museum of Contemporary Art in Tehran. But a striking portrait by Francis Bacon, which is thought never previously to have gone on public display, is being rushed to Britain as a highlight of a new exhibition of the artist's works.

For 25 years, it has languished in the vaults of the Museum of Contemporary Art in Tehran. But a striking portrait by Francis Bacon, which is thought never previously to have gone on public display, is being rushed to Britain as a highlight of a new exhibition of the artist's works.

The deal with Iran was clinched after months of negotiations - although there is still a question mark over whether the work will arrive in time for this weekend's opening of Francis Bacon: Portraits and Heads at the Scottish National Gallery of Modern Art in Edinburgh.

The show is the last scheduled to take place for four years after the Bacon estate decided on a moratorium on loans pending the centenary of the artist's birth in 2009.

Reclining Man with Sculpture, 1960-1961 was owned by the British collector, the Marquess of Dufferin and Ava, but was sold to the wife of the late Shah of Iran in the 1970s who founded her own gallery. But many of the Western paintings in her extraordinary collection ended up in storage when the fundamentalists seized power in 1979 and took control of what became known as the Tehran Museum of Contemporary Art.

Andrea Rose, director of visual arts at the British Council, spotted this portrait in the museum's vaults when she was visiting Iran two years ago.

The portrait is thought to be of Peter Lacy, a former RAF pilot who was Bacon's lover. They had a tense and violent relationship, although Lacy is often described as the love of Bacon's life.