A long-lost painting of Jesus Christ by old master Leonardo Da Vinci has sold for $US450 million – more than double the previous mark for any work of art at auction.

The haunting image, entitled Salvator Mundi – or Saviour of the World – is now officially the world’s most expensive painting, totally eclipsing nearest competitors by Pablo Picasso and Willem de Kooning.

In Australian dollars, the painting sold for $592 million, equal to around 1000 high-end Ferraris, well above the cost of a brand new Airbus A380, and about a third of the value of Buckingham Palace in London – where it might have been hanging today had history taken a different turn.

To give it a topical Aussie spin, the proceeds from the sale of Leonardo’s masterpiece could have paid for another five same-sex marriage postal surveys.

Or, indeed, two federal elections, with some change left over.

Salvator Mundi was verified as an authentic da Vinci after a long period of painstaking research, inquiry and restoration.

Auction house Christie’s had ‘only’ expected to get $US100 million for the painting.

In the event, though, the tense, thrilling auction in New York on Wednesday (Thursday AEDT) saw bids soar past this figure and into the high 300 millions.

It seemed as if the auction would end there – more than three times the expected price – and the auctioneer was poised to bring his hammer down at around $370 million.

But then a last-minute bid pushed the price up by a staggering $30 million in one go, resulting in a final sale price of more than four times what Christie’s had expected.

As the hammer came down, the auction room erupted with applause. Christie’s did not reveal the identity of the successful bidder.

Picasso’s Women of Algiers held the previous record for a painting sold by auction, going for $US179 million in 2015.

A strange journey through history

Salvator Mundi‘s journey to becoming the world’s most valuable painting was a long and strange one.

Finished around 1500, by the mid-1600s Salvator Mundi had become part of King Charles I of England’s private collection. In the chaos of the English Civil War – which resulted in Charles having his head chopped off and England becoming (briefly) a republic – the painting was lost.

It resurfaced in 1900, by which time it was thought to be a minor work by a Leonardo imitator. It sold at auction in 1958 for just £45.

Twelve years ago a painstaking process of restoration and verification led to the expert consensus that Salvator Mundi was indeed an original da Vinci.

Among other things, its authenticity rested on evidence that the artist had painstakingly planned the Christ figure’s head by tracing it from a sketch – but had taken a more improvisational approach to the rest of the figure’s body. This, apparently, is a technique typical of Leonardo.

The Christ figure’s resemblance to other Leonardo figures – notably his John the Baptist, as well as his most famous creation of all, the Mona Lisa – is unmistakeable.

Leonardo’s John the Baptist resembles the Christ figure in Salvator Mundi.

“Salvator Mundi  is a painting of the most iconic figure in the world by the most important artist of all time,” said Loic Gouzer, chairman of post-war and contemporary art at Christie’s in New York.

“The opportunity to bring this masterpiece to the market is an honour that comes around once in a lifetime. Despite being created approximately 500 years ago, the work of Leonardo is just as influential to the art that is being created today as it was in the 15th and 16th centuries.”

While he may be the most influential and revered artist of all time, only 15 verified paintings by Leonardo da Vinci survive. This extreme rarity explains the extraordinary sale price, and led art critic Alastair Sooke to liken discovering a new da Vinci painting to “finding a new planet”.