White House adviser Tony Blinken says there is evidence that Russia is preparing to deliver more powerful rocket launchers to separatist rebels in eastern Ukraine.
Western powers have accused pro-Russian rebels in the area of shooting down Malaysia Airlines flight MH17 with a rocket.
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Ratings agency Moody's said victory for Brexit would "herald a prolonged period of uncertainty" for the UK.
Five people were taken to hospital after walking on coals at a Tony Robbins seminar called 'Unleash the Power Within'.
An emergency meeting will be held today to discuss the Scottish government's next steps following the UK's decision to leave the EU.