The US State Department is in conversations with the Ukraine government to stipulate requirements for a humanitarian aid convoy from Russia to cross borders.
Deputy spokesperson Marie Harf said the International Red Cross would take control of the aid and distribute it once the convoy crossed the border into Ukraine.
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The violence began after a counter-protester allegedly doused a female rally organiser with pepper spray.
As temperatures climb through the day, the warmest spots are likely to be across western parts of Northern Ireland and western Scotland.
Boris Johnson and Amber Rudd have both criticised social media giants for failing to detect and remove extremist material online.