угроза усиления санкций

The White House said Friday night that Mr. Obama had called Chancellor Angela Merkel of Germany and President François Hollande of France, and that the three leaders had agreed the United States and the European Union would impose additional sanctions “should Russia fail to take immediate, concrete steps to de-escalate the situation in eastern Ukraine.”
http://www.nytimes.com/2014/06/22/world/europe/ukraine.html