Russian expert James Nixey told ITV News that he does not think the meeting between Russian President Putin and Prime Minister Cameron will "result in a substantial change in position."
He says there is still a "fundamental divergence of values" on the issue, and he does not think "one pre-judo meeting" will accomplish.
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Days of government bombardment in rebel-held eastern Ghouta have now left more than 500 people dead, observers say.
A cold and sunny day tomorrow
Actress Emma Chambers - star of Notting Hill and The Vicar of Dibley - has died, her agency has confirmed.