Greek police have unearthed a painting by Spanish artist Pablo Picasso that was stolen more than nine years ago in a daring heist at the National Gallery in Athens.

The Picasso painting, Woman’s head, was found with a damaged work by Dutch painter Piet Mondrian in a warehouse about 50 kilometres from Athens.

Both were taken, along with a third artwork, after being stripped from their frames in elaborate 2012 raid that allegedly took just seven minutes. The thieves also initially grabbed a fourth work, also by Mondrian, but abandoned it as they fled.

A 49-year-old man was alleged to be the thief, Greek media reported on Monday (local time).

The 1939 Picasso work is estimated to be worth 16.5 million euros ($A26.1 million).

But it has even more special significance for Greece, as the artist gifted  it to the nation personally to reward its resistance against the Nazis during World War II.

The Culture Ministry in Athens confirmed the find.

More details were to be revealed during at a media briefing on Tuesday.

The hunt for Woman’s head resumed in earnest last February, after experts realised it had never turned up on the black market – and had therefore likely never left Greece.

-with AAP