The dealer, who was not named by police, was on his way to meet an art collector in the 11th arrondissement of Paris.

Police said that the dealer hailed a taxi and put the painting in the boot — but then “forgot” about it. He tried to locate the cab again but failed, and has now filed a complaint of theft with police.

The artwork is by Argentina-born Italian sculptor and painter Lucio Fontana (1899–1968), entitled “Concetto spaziale” (Spatial concept).

The work is one of a series of abstracts he made featuring the piercing of the canvas to create an actual dimension of space and using light.

He became known for founding the spacialist movement.