As the Louvre museum prepares to unveil a blockbuster exhibition of works by Leonardo da Vinci on Thursday, mystery surrounds whether the show will include the world's most expensive painting -- Salvator Mundi, attributed to the master painter.
It is unlikely, but organisers have not ruled out a last-minute appearance by the painting that sold for $450 million (400 million euros) at a 2017 Christie's auction.
The work, in which Jesus Christ is depicted emerging from darkness, blessing the world with one hand while holding a transparent globe in the other, has not been seen in public since its sale.
The Wall Street Journal first reported that the painting was bought by Saudi prince Badr bin Abdullah, who had acted in the name of the crown prince, Mohammed bin Salman, known by his initials MBS.
Riyadh never confirmed or denied that report.
But the culture ministry of the United Arab Emirates said the Gulf State was the owner and that the painting was to go on display at the Louvre Abu Dhabi in September 2018.
Then, to widespread surprise, the UAE said it was postponing the hanging.
Kenny Schachter, a prominent London art dealer and critic, says the work is riding the waves aboard MBS's massive yacht, the Serene, citing several sources including two involved in the sale.
Schachter claimed on the website Artnews that the painting "was whisked away in the middle of the night on MBS's plane" and flown to the yacht.
Other rumours place the painting at a Geneva museum.
The Louvre's request to Abu Dhabi for the loan of the painting is still pending.
Debate over attribution
Adding to the mystery is uncertainty over the work's authenticity.
Many art experts are split over whether the painting is a genuine Da Vinci, with some arguing it was not painted by the Renaissance master personally but by one of the apprentices in his studio.
To support this theory, they say one of Jesus's fingers is badly executed, and note that the painting is not mentioned in any of Leonardo's correspondence or that of his contemporaries.
But Dianne Modestini, the American restorer who rescued the work from an extremely bad condition, is categorical that the painting is authentic.
Another version, somewhat larger, is in the show, among around 22 existing paintings on the theme of Jesus as the "Saviour of the World", according to the curator, Vincent Delieuvin.
The question of whether Leonardo's Salvator Mundi makes it into the show may have broader geopolitical import. According to Schachter, the work may not find a permanent home until Saudi Arabia succeeds in transforming its northern Al-'Ula region into a tourist destination.
The exhibition runs until February 24.