William Hague has said Russia has "lost control" of the situation in Ukraine, where deadly clashes have seen dozens killed in the last week.
Speaking to the Daily Telegraph, the Foreign Secretary said:
“President Putin seems to have unleashed forces that he cannot control. Armed thugs with modern weapons are stirring old tensions and stoking new hatreds. The deaths in Mariupol, Slavyansk and Odessa are a stark warning that this plan is spiralling out of control.”
Mr Hague also claimed Russia's conduct towards Ukraine was more evidence of "bullying" behaviour towards its neighbouring countries.
"There is a pattern of how the Russians behave towards their neighbours, and it needs to be stopped," he said.