An early Lucian Freud painting worth at least £300,000 has been identified by the BBC, despite the artist's own denials that it was his work.
The painting, by the acclaimed portrait artist who died in 2011, was identified by BBC One show Fake Or Fortune.
Experts at Christie's auction house claimed it to be a Freud in 1985, but the artist denied it was his work.
However, notes uncovered from the artist's former solicitor and further analysis prove the painting was by him.
It is claimed the artist's reticence in acknowledging the work was down to the fact that it was originally owned by Denis Wirth-Miller, an artist with whom Freud had a long-running feud. Denying authorship meant it was impossible for it to be sold under his name.
Fake Or Fortune presenters Fiona Bruce and art historian Philip Mould had the breakthrough when they spoke to Freud's solicitor, who found a note in her files of a phone conversation with the artist from 2006.
Freud apparently said he had started the painting, but it had actually been completed by someone else and for this reason, he would not acknowledge it as his own work.
Now after analysis of the techniques and materials used in the painting, three Freud experts said they believed the painting was solely by him, and was likely to have been completed in 1939.
London-based designer Jon Turner, who inherited the painting of a man in a black cravat, said he spent years trying to authenticate the portrait but he believed Freud had continued to prevent his investigations.
Mr Mould, who valued the painting at £300,000 or more, said: "It was a novel and gargantuan task to overturn the reported views of the artist.
"It was different from anything we'd taken on until now - we had never had to arm-wrestle with the words of an artist beyond the grave.
"It was all the more frustrating as the more I worked on the picture and Fiona was able to add the background with her enquiries, the more I felt confident about it being entirely by Freud."
A grandson of the psycho-analyst Sigmund Freud and the son of an architect, the artist was born in Berlin in 1922 and fled from Nazi Germany to Britain with his Jewish family in 1933, when he was 10.
After attending art school as a teenager, Freud was soon recognised as a brilliant talent. He said his work was purely autobiographical - painting "the people that interest me and that I care about and think about in rooms I live in and know".
Ms Bruce added: "As this investigation progressed we had to investigate Freud the man as much as the painting. He was an extraordinary and controversial character."
It is not the first time the BBC programme has made such a discovery. In 2014, a painting thought to be by Russian-born artist Marc Chagall bought for £100,000, was found to be a fake and had to be destroyed.
Fake or Fortune? is broadcast on Sundays at 20:00 BST on BBC One. It is available nationwide for seven days thereafter on the iPlayer.