MOSCOW (AP) — The U.S. Embassy in Moscow says the condition of an American man held on spying charges in Russia has worsened.

The Embassy said on Twitter Monday that Russian authorities had rejected a request to send a doctor to examine Paul Whelan. It said Whelan has received basic medical assistance, but that his condition has deteriorated.

Whelan, who also holds British, Irish and Canadian citizenship, was arrested in a hotel room in Moscow in December and charged with espionage, which carries up to 20 years in prison.

The former U.S. Marine, who denies the charges, has publicly complained of poor prison conditions and has said his life is in danger.

Russia's Deputy Foreign Minister Sergei Ryabkov on Monday denied plans to exchange Whelan for Russians in U.S. custody.

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