The mother of British journalist Kieron Bryan said she hopes "common sense, and a sense of fair play and justice" will prevail.
Speaking as at a silent protest outside the Russian Embassy in London, Ann Bryan said the country has made its point and said her son should be released.
"Punishment should fit the crime and for what happened that day I think they've more than served their punishment," she said.Adding: "I just hope that common sense, and a sense of fair play and justice, will come out of this."
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Cloud and outbreaks of rain will ease away eastwards during the morning, clearing the east coast around midday with sunny spells developing.
Police and emergency services are attending the scene.
Rebel-held east remains at risk while the pumping station supplying the western part of the city is once again in operation.