A high-profile prisoner swap between Russia and the US that may include jailed journalist Evan Gershkovich is due to take place, according to US media.

The exchange, which could also see Kremlin assassins sent back to Russia, would be the largest prisoner exchange between Russia and the US since the Cold War.

Fox News national security correspondent reported on Thursday that Mr Gershkovich, who was sentenced to 16 years on espionage charges last month, could return to the US as early as today.

Hopes were raised on Wednesday after a series of mysterious movements of prominent Western prisoners prompted speculation that Vladimir Putin had agreed to swap them for Russians held in the West.

Sources in Ukraine suggested that Vladimir Kara-Murza, a Russian-British opposition activist, and Paul Whelan, a former US marine, could also be among those being released from Russian custody.

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