A French documentary has cast fresh doubts over the world's most expensive painting, the "Salvator Mundi" credited to Leonardo da Vinci, revealing a resulting diplomatic tussle between France and its Saudi owner.
The painting of Jesus Christ, nicknamed the "male Mona Lisa", was sold at a 2017 Christies auction in New York for a record $450 million.
Its secret buyer was later revealed to be Saudi crown prince Mohammed bin Salman, though this is still denied in Riyadh.
There have long been questions over whether it was entirely the work of da Vinci. Now a documentary, "The Savior for Sale" by filmmaker Antoine Vitkine, to be premiered on French TV next week, sets out to reveal what was going on behind the scenes.
In the film, senior officials from President Emmanuel Macron's government, appearing under pseudonyms, confirm that the Louvre's scientific analysis of the painting concluded that while it was produced in da Vinci's workshop, the master himself only "contributed" to the painting.
This apparently went down badly with the Saudis.
"Things turned incomprehensible," says one of the French officials in the film. "The request by "MBS" (bin Salman) was very clear: show the Salvator Mundi next to the Mona Lisa, and present it as 100 percent a da Vinci."
Macron ultimately decided to reject bin Salman's request, leaving it to the Louvre to negotiate with the Saudis on how the painting should be presented in their retrospective, said the documentary. No deal was concluded and the museum has refused to comment on the case.