A French court on Friday rejected a request for an injunction against the auction in Paris of ceremonial masks originating from Arizona's Hopi tribe, despite opponents saying the sale amounted to "sacrilege".
A French lawyer for the tribe, Pierre Servan-Schreiber, told AFP the court had refused to halt the sale of around 70 brightly coloured "Kachina" visages and headdresses by auction house Neret-Minet, which was due to start at 1230 GMT.
High-profile figures including actor Robert Redford and the US ambassador to Paris had called for the sale to be cancelled or delayed, saying the masks are sacred objects to the Native American tribe.
The auction has outraged members of the 18,000-strong Hopi tribe, who say the items are blessed with divine spirits. Two Arizona museums had also called for the sale to be cancelled.
Neret-Minet said there were no grounds to halt the sale because the items were acquired legally by a French collector during a 30-year residence in the United States.
In a letter of support, Hollywood star Redford wrote that the masks "belong to the Hopi and the Hopi alone".
"To auction these would be, in my opinion, a sacrilege -- a criminal gesture that contains grave moral repercussions.
"I would hope that these sacred items can be returned to the Hopi tribe where they belong. They are not for auction," added Redford, who described himself "as a close friend" of the tribe.
In a statement released late Thursday, US ambassador to Paris Charles Rivkin had also urged a postponement of the sale.
"Hopi representatives have requested a delay in the sale in order to better identify and determine the provenance of the objects," he said. "A delay would allow the creators of these sacred objects the chance to determine their possible rights."
The sale of sacred Native American artefacts has been outlawed in the United States since 1990 -- legislation which has allowed the Hopi tribe to recover items held by American museums in the past -- but the law does not extend to sales overseas.
Servan-Schreiber had argued that French law also bans the sale of certain sacred objects out of "strict observance of respect for the dead."
Hopi president LeRoy Shingoitewa told AFP recently that the auction was highly offensive.
"The objects that are being auctioned are considered sacred because they are part of our religious beliefs," he said. "They are used in a manner that helps us to help our people in this world to get harmony, to get blessings.
"These are not considered among our people to be art," he said "We want to stop the auction. We want the sacred objects returned back to the Hopi."