Gershkovich, a reporter for the Wall Street Journal, was detained by the Federal Security Service (FSB) on March 29 in the Urals city of Yekaterinburg on charges of espionage that carry up to 20 years in prison.

Gershkovich, wearing jeans with a dark shirt over a white T-shirt, smiled quizzically from a glass box in court at journalists who were allowed to photograph him before the closed hearing. FSB officers, some in masks, looked on.

Judge Yuri Pasyunin said the Moscow city court had decided to leave without change an earlier court decision to extend his pre-trial detention.

“The appeal complaint is left without satisfaction,” Pasyunin said. Reporters were allowed to listen to the court’s decision via a video link in a different part of the court house.

The decision essentially means that Gershkovich, 32, will remain in detention. No date has been set for his trial.

Gershkovich is the first American journalist to be detained on spy charges in Russia since the Cold War. American diplomats attended the Moscow courthouse.

Russia has said Gershkovich, the first American journalist to be detained on such charges since the Cold War, was caught “red-handed” while the FSB, the main successor to the Soviet-era KGB, said he was trying to obtain military secrets.

The White House has called the charges “ridiculous” and President Joe Biden has said Gershkovich’s detention is “totally illegal”. The Journal denies the charges and has called for his immediate release, as has his family.

Russia has yet to make any evidence in the case public. Tuesday’s hearing was closed due to the case containing materials classified as secret.

A fluent Russian-speaker born to Soviet emigres and raised in New Jersey, Gershkovich moved to Moscow in late 2017 to join the English-language Moscow Times, and subsequently worked for the French news agency Agence France-Presse.

Russia announced the start of its “special military operation” in February 2022, just as Gershkovich was in London, about to return to Russia to join the Journal’s Moscow bureau.

It was decided that he would live in London but travel to Russia frequently for reporting trips, as a correspondent accredited with the Foreign Ministry.

By Guy Faulconbridge

(Reporting by Guy Faulconbridge; Editing by Mark Trevelyan and Gareth Jones)