An elderly German recluse has said he is prepared to return precious paintings stolen by the Nazis from Jewish families, including a priceless Matisse.

Cornelius Gurlitt, 81, had stashed about 1,400 long-lost works by European masters in his Munich apartment, and more than 200 paintings and sketches in a home in Salzburg, Austria.

The spectacular Munich hoard was discovered by German authorities by chance in 2012 and only came to public attention in a magazine article published in November.

His spokesman said Mr Gurlitt had ordered his legal team to hand back works believed to have been stolen or extorted from Jewish families as part of the systematic looting of art collections by Nazis during World War II.

"Should there be the well-founded suspicion that works are looted art then please give them back to their Jewish owners," Mr Gurlitt told his lawyer, according to a statement by his spokesman Stephan Holzinger.

Henri Matisse's Sitting Woman will be the first work returned, Mr Holzinger said, to the heirs of renowned Paris art collector Paul Rosenberg.

The painting shows a stout, dark-haired woman in a floral dress sitting in a chair in a room with vibrant wall coverings.

The Nazis stole the work from Rosenberg and it was kept for a time in the vast looted art collection of Hermann Goering, the Gestapo secret police founder and air force chief.

"We are very confident about reaching a deal on the return in the coming days," Mr Holzinger said.

Mr Gurlitt's father Hildebrand acquired the paintings in the 1930s and 1940s, when he worked as an art dealer tasked by the Nazis with selling stolen works and art the Hitler regime deemed "degenerate".

A task force appointed to research the origins of the Gurlitt works said it suspected 458 were stolen or extorted from Jewish owners under Hitler.

It said 380 other pieces were believed to have been confiscated as part of a campaign against what the Nazis considered "degenerate" art, mainly from public collections and museums.

Germany came under fire for keeping the Gurlitt find under wraps and faces renewed pressure over its post-World War II restitution efforts.

Lawmakers are currently debating a law to ditch a 30-year statute of limitations that has provided cover for people in possession of contested artwork.

AFP