NATO Secretary General Anders Fogh Rasmussen has spoken of an alarming build-up of Russian ground and air forces close to the border with Ukraine.
He condemned Russia for sending a "so-called humanitarian convoy" into Ukraine without the consent of the Ukrainian authorities.
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The IMF's forecast for global growth has been cut to 3.1% - a fifth successive year of declining growth, the weakest performance since 2009.
Coronation Street actor Ryan Thomas is to quit the show after more than 15 years.
Fresh violence has erupted in the West Bank following the death of a 13-year-old boy, sparking fears of a new Palestinian uprising.