A Moscow court on Tuesday extended for three months the detention of a former U.S. consular employee accused of gathering information for Washington on the war in Ukraine and other issues, Tass news agency reported.

Tass quoted the press service of the Lefortovo court as saying that a three-month extension requested by investigators until Nov. 23 had been granted for the detention of Robert Shonov, a Russian national.

The Tass report said Shonov had acknowledged his guilt in passing on information to U.S. diplomats.

U.S. State Department Spokesperson Matthew Miller on Monday repeated the U.S. position that the allegations against Shonov were "wholly without merit."

Miller said the action against Shonov "only highlights the increasingly repressive actions the Russian government is taking against its own citizens".

Shonov was employed by the U.S. Consulate General in the eastern Russian city of Vladivostok for more than 25 years until Russia in 2021 ordered the termination of the U.S. mission's local staff.

Washington says he was subsequently employed via a company contracted to the U.S. embassy to summarize news reports.

Russia's FSB security service has said it plans to question U.S. embassy employees who were in contact with Shonov, who has been under arrest since May.

The FSB said Shonov relayed information to U.S. embassy staffers in Moscow on how Russia's conscription campaign was impacting political discontent ahead of the 2024 presidential election in Russia.

Miller said Washington was aware the FSB had also summoned two diplomats working at the U.S. embassy in Moscow in connection to the case.

(Reporting by Reuters; Editing by Ron Popeski and Sandra Maler)