A long-lost painting by 17th-century Flemish master Peter Paul Rubens sold at auction in France today for almost €3 million - well beyond its asking price.

The work, of Jesus Christ on the cross and painted in 1613, was unearthed by auctioneer Jean-Pierre Osenat in a Paris mansion last year.

Osenat, whose auction house sold the painting for €2.94m ($5.5m) against an expected €1-2m, found the painting as he was preparing the property to be sold.

He told AFP earlier this year the picture was “a masterpiece” which was painted by Rubens when he was “at the height of his talent”.

The auction house said in its promotional material that very little was known of the painting - only that a peer of Rubens had made an engraving of it.

Later historians described this engraving and, despite having never seen the painting, catalogued its existence.

It was bought by 19th-century French academic painter William-Adolphe Bouguereau and passed down through his family, according to the auction house.

The painting was authenticated by German art historian Nils Buttner, known for his research on the master of the Flemish Baroque, Osenat said.

Its provenance was certified through methods including X-ray imaging and pigment analysis, he added.

“It’s the very beginning of Baroque painting, depicting a crucified Christ, isolated, luminous and standing out vividly against a dark and threatening sky,” he said.

Although Rubens produced many works for the Church, the painting, measuring 105.5 by 72.5cm, was likely to have been created for a private collector.

-Agence France-Presse