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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Unpaid internships should be banned to prevent young people missing out on jobs in top professions, a new report has said.
The study by the National Childbirth Trust and National Federation of Women's Institutes found a lack of staff left some women frightened.
Extracts released by 10 Downing Street suggest Mrs May will say the UK will not settle for a "half-in, half-out" policy.