LISBON (AFP).- Portugal has seized a trove of contemporary artwork, including paintings by Joan Miro and Piet Mondrian, from its debt-riddled owner, the government said on Tuesday.

"There has been a court ruling to this effect," a spokeswoman for the Culture Ministry said, confirming media reports.

For months, three Portuguese banks had tried but failed to seize the art collection from Portuguese businessman Jose Berardo. The 75-year-old had offered the works as collateral for his debt which totalled nearly one billion euros ($1.1 billion). The lenders refused to comment on the case when contacted by AFP.

The modern art collection of more than 900 works which includes, besides Miro and Mondrian, other famous artists such as Gerhard Richter and Francis Bacon, was valued in 2006 at 316 million euros.

But the collection could have doubled in value since then given the growth in the art market. Bacon's "Self-Portrait", for example, sold for over 17 million euros when it was auctioned at Southeby's last month.

Much of the Berardo collection has been on display to the public in Lisbon's museums since 2006, under an agreement between the businessman and the galleries, which put them out of the banks' reach.

It is unclear if the lenders will obtain possession of the collection, which for now remains in the state's custody, according to Portuguese media reports.

It is not the first time Berardo's assets have been seized. According to the media, Portugal had already taken a property of his on the island of Madeira which he had left in 1963 to make his fortune in South Africa.

Berardo had borrowed a total of 962 million euros from state bank Caixa geral de depositos (CGD), the BCP (Banco comercial portugues) and the former bank Espirito Santo, now Novo Banco. He acquired shares of BCP to become its third largest shareholder.

© Agence France-Presse