Russian prosecutors have sent the case of detained U.S. reporter Evan Gershkovich to court after concluding that he collected information for the U.S. Central Intelligence Agency about a Russian tank factory, they said in a statement on Thursday.

The office of Russia's General Prosecutor said it had approved the indictment and that Gershkovich's criminal case would be heard by a court in the Urals city of Yekaterinburg, where the reporter was arrested in March 2023 on suspicion of espionage.

It did not say when the case would be heard.

Gershkovich and his employer reject the espionage allegation as false and the Biden administration has demanded that Moscow release him.

"The investigation has established and confirmed with documentary evidence that Gershkovich, an American journalist for The Wall Street Journal, on the instructions of the CIA, collected secret information in the Sverdlovsk region in March 2023 about the activities of the defence plant NPK Uralvagonzavod JSC on the production and repair of military equipment," the prosecutors' statement said.

"Gershkovich carried out the illegal actions using painstaking conspiratorial methods," it said.