An art gallery in Florence, Italy, has pleaded for Germany to return a "masterpiece" that was looted by Nazi soldiers in 1944.

Still life artwork "Vase of Flowers," painted by 18th century Dutch artist Jan van Huysum, was stolen from Florence by German troops during the Second World War. Eike Schmidt, director of the city's Uffizi Galleries, said in a statement on Tuesday that the beginning of the new year was a good opportunity for the painting to be given back.

"Because of this affair that affects the heritage of the Uffizi Galleries, the wounds of the Second World War and Nazi terror are not yet healed," he said.

The painting disappeared for several decades after being moved to a castle in the northern Italian province of Bolzano, resurfacing in the 1990s. Schmidt claimed "various intermediaries" have since attempted to demand "absurd" ransoms for the painting's return.

"Germany still has a moral duty to return this work to our museum, and I hope that the German state can do it as soon as possible – together, obviously, with every work of art looted by the Nazi army," he said.

According to the gallery, van Huysum's painting is currently being kept in the private collection of a German family, who have refused "numerous requests from the Italian state" to visit the Uffizi museum.

A black and white replica is currently hanging in place of the original piece, along with signs that read "stolen" in Italian, English and French.