Reporters were briefly allowed to film US journalist Evan Gershkovich on Wednesday before the start of his trial in the Russian city of Yekaterinburg on charges of espionage that he denies.
Gershkovich was seen standing in a glass box, with a shaved head.
Gershkovich, a reporter for the Wall Street Journal, is accused by prosecutors of gathering secret information on a company that manufactures tanks for Russia's war in Ukraine. If convicted, he faces a sentence of up to 20 years.
He, his newspaper and the US government all reject the allegations and say that he was just doing his job as a reporter accredited by Russia's Foreign Ministry to work there.
Against the background of the Ukraine war, he and other Americans detained in Russia have been caught up in the most serious crisis between Moscow and Washington for more than 60 years.
President Vladimir Putin has said Russia is open to the idea of a prisoner exchange involving Gershkovich and that contacts with the United States have taken place, but they must remain secret.
The US has accused Russia of conducting "hostage diplomacy". It has designated Gershkovich and another jailed American, Paul Whelan, as "wrongfully detained" and says it is committed to bringing them home.
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