NEW YORK (Reuters) - NEW YORK - Hollywood actor Nicolas Cage has agreed to turn over a rare stolen dinosaur skull he bought for US$276,000 in 2007 to United States authorities, so that it can be returned to the Mongolian government.

The office of Mr Preet Bharara, the US Attorney in Manhattan, filed a civil forfeiture complaint last week to take possession of the Tyrannosaurus bataar skull, which will be repatriated to Mongolia.

The lawsuit did not specifically name Cage as the owner, but his publicist confirmed that the actor bought the skull in March 2007 from a Beverly Hills gallery, I.M. Chait.

Cage is not accused of wrongdoing, and the authorities said he voluntarily agreed to turn over the skull after learning of the circumstances.

His publicist Alex Schack said in an email that the actor received a certificate of authenticity from the gallery and was first contacted by US authorities in July 2014, when the Department of Homeland Security informed him that the skull might have been stolen.

Following a determination by investigators that the skull in fact had been taken illegally from Mongolia, Cage agreed to hand it over, Schack said.

He outbid fellow star Leonardo DiCaprio for the skull, according to prior news reports. The I.M. Chait gallery had previously purchased and sold an illegally smuggled duck-billed dinosaur skeleton from convicted paleontologist Eric Prokopi, whom Mr Bharara called a "one-man black market in prehistoric fossils". The Chait gallery has not been accused of wrongdoing.

It was unclear whether the Cage skull was specifically connected to Prokopi, who pleaded guilty in December 2012 to smuggling a nearly complete Tyrannosaurus bataar skeleton out of Mongolia's Gobi desert and was later sentenced to three months in prison.

As part of his guilty plea, he helped prosecutors recover at least 17 other dinosaur fossils.

Assistant US Attorney Martin Bell, who prosecuted Prokopi, was also the lead government lawyer in the Cage case, according to court records.

The Tyrannosaurus bataar, like its more famous relative Tyrannosaurus rex, was a carnivore that lived approximately 70 million years ago. Its remains have been discovered only in Mongolia, which criminalised the export of dinosaur fossils in 1924.

Since 2012, Mr Bharara's office has recovered more than a dozen Mongolian fossils, including three full Tyrannosaurus bataar skeletons.

"Each of these fossils represents a culturally and scientifically important artefact looted from its rightful owner," Mr Bharara said in a statement last week.