Court rules in favour of auctioneers despite plea from Native American tribe and US ambassador that the masks are sacred

A Paris auction house has gone ahead with a contested sale of dozens of Native American tribal masks after winning a court ruling, despite appeals for a delay by the Hopi tribe, its supporters and the US government.

Shortly after the court announced its decision, auctioneers began selling dozens of brilliantly coloured masks made of wood, leather, horsehair and feathers at the Drouot auction house on Friday.

The auctioneer argued that blocking the sale would have tremendous implications and potentially force French museums to empty their collections. Protesters repeatedly disrupted the sales.

The Hopi want the masks returned, insisting they have a special status and are more than art: they represent their dead ancestors' spirits. The Hopi, a tribe whose territory is surrounded by Arizona, nurture the masks as if they are the living dead. The actor Robert Redford was among those calling for the sale to be halted.

In its ruling, the court noted that the Hopi ascribe "sacred value" to the masks but "clearly they cannot be assimilated to human bodies or elements of bodies of humans who exist or existed" – the sale of which would be banned in France.

The court also alluded to a 1978 US law, the American Indian Religious Freedom Act, and wrote "no provisions banning the sale outside the United States of objects used in religious ceremonies or susceptible to be is applicable in France".

Advocates for the Hopi expressed dismay. "This decision is very disappointing, since the masks will be sold and dispersed," the tribe's French lawyer, Pierre Servan-Schreiber, said outside the courtroom. "The Hopi tribe will be extremely saddened by the decision, especially since the judgment recognises that these masks have a sacred value. The judge considers that the imminent damage (to the masks) is not sufficiently strong."

Jean-Patrick Razon, France director for Survival International, an advocacy group that supports tribal peoples, also expressed disappointment.

"The Hopi people have been pillaged throughout their history. We despoiled their land, we killed them, we violated their souls and it continues. Now, their ritual objects are being put up for auction," Razon said.

The Hopi's lawyers filed a request with the Council of Sales, the French auction market authority, to suspend the sale, Servan-Schreiber said, but a council spokeswoman said it had no legal grounds to intervene.

The US ambassador to France, Charles Rivkin, tweeted: "I am saddened to learn that Hopi sacred cultural objects are being put up for auction today in Paris." On Thursday, he sent a letter to the French government and the auction house asking for a delay to allow better consideration of the tribe's concerns.

Hollywood star Redford joined the effort, writing a letter calling the sales a "sacrilege" – even a "criminal gesture".

Auctioneer Gilles Neret-Minet said he would not gloat over the ruling "but I'm happy that French law was respected".

"I am also very concerned about the Hopi's sadness, but you cannot break property law," he said. "These are in (private) collections in Europe: they are no longer sacred. When objects are in private collections, even in the United States, they are desacralised."

Neret-Minet said the auction house had received "serious threats" before the auction.

The 70 objects, mainly Hopi, went on display at Drouot for the first time as the court battle kicked off on Thursday, offering a rare public glimpse of such works in Europe. They date from the late 19th century and early 20th century, and are thought to have been taken from a northern Arizona reservation in the 1930s and 1940s. The most expensive single mask is estimated to be worth at least €50,000 (£43,000).

The masks are striking – surreal faces made from wood, leather, horsehair and feathers, painted in vivid pigments of red, blue, yellow and orange. Hopi representatives contend the items were stolen at some point and wanted the auction house to prove otherwise.

Disputes over art ownership, demands for restitution, and arguments over whether sacred objects should be sold are nothing new.

There has been a decades-long dispute between the British Museum and Greece over the Parthenon marbles, which Scottish diplomat Lord Elgin removed from the Parthenon in the 19th century. Greece wants them back but opponents fear that would open the floodgates, forcing western museums to send home thousands of artefacts.