US Secretary of State John Kerry warned Russia that it must not intervene in Ukraine under the "pretext of peacekeeping", his department said.
The statement follows Russia's version of the call, in which its Foreign Minister Sergei Lavrov was said to have called for urgent measures to avert a "humanitarian catastrophe" in the east of the country.
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Patients are being left "belittled and bewildered" as medical staff try to deal with overstretched systems, the BMA will warn.
One tenant confronted the leader of Camden Council as tensions rise in evacuation of Chalcots estate.
The teenager, who cannot be named for legal reasons, is alleged to have attacked the girl in a Manchester park on Saturday evening.