A 500-year-old painting by Leonardo da Vinci has sold for a record $A592 million.
The painting went up for auction today after Russian billionaire Dmitry Rybolovlev decided to sell it.
The oil painting depicting Christ holding a crystal orb, called Salvator Mundi, Italian for "Savior of the World", is one of fewer than 20 paintings by da Vinci known to exist, according to Christie's, the auction house conducting the sale.
The painting was valued at $US100 million which is where they started the bidding.
There were gasps from the audience at the auction as the price continued to rise.
The painting had been valued at $US100 million by numerous auctioneers.
The bidding was between two private clients, represented by Christie's Francois de Poortere and Alex Rotter.
Mr Rotter had the winning bid when his telephone client offered $US400 million for the painting.
In 1958, the painting was sold for $60 at an auction in London.
"I can hardly convey how exciting it is for those of us directly involved in its sale," said Christie's specialist Alan Wintermute.
"The word masterpiece barely begins to convey the rarity, importance and sublime beauty of Leonardo's painting," Mr Wintermute said.
He called it "the Holy Grail of old master paintings".
A backer of the auction guaranteed a bid of at least $100 million (85 million euros).
Experts have said it might be worth more, except for its generally poor state of preservation and lingering questions about its authenticity.
The 66cm painting dates from around 1500 and shows Christ dressed in Renaissance-style robes, his right hand raised in blessing as his left hand holds a crystal sphere.
The painting's history is as mysterious as Jesus's enigmatic gaze, which invites comparison to a better-known Leonardo work, the Mona Lisa.
Salvator Mundi was owned by King Charles I of England in the mid-1600s and was auctioned by the son of the Duke of Buckingham in 1763.
It then disappeared from view until 1900, when it resurfaced and was acquired by a British collector.
At the time, it was thought to be a work of a da Vinci disciple, rather than by the master himself.
The painting was sold again in 1958 and then acquired in 2005, badly damaged and partly painted-over, by a consortium of art dealers who paid less than $10,000 (8445 euros).
The art dealers restored the painting extensively and documented its authenticity as a work by da Vinci.
The work's current owner is Russian billionaire Dmitry Rybolovlev, who bought it in 2013 for $127.5 million (108 million euros) in a private sale that became the subject of a continuing lawsuit.
Christie's says most scholars believe it is a work by Leonardo, though some critics have questioned that determination while others have said it was so extensively restored that it is probably more akin to a copy than an original.
- With Wires