Kerry accuses Russia of inaction in helping to ease tension in eastern Ukraine

Secretary of State John Kerry on Thursday accused Russia of inaction in helping to ease the tense situation in eastern Ukraine, warning that the United States is ready to impose additional sanctions in response.

In a statement made to the press, the top American envoy alleged that Russia has refused to take "a single concrete step in the right direction" for the past seven days since the U.S., the European Union, Russia and Ukraine agreed in Geneva, Switzerland, to takes steps to de-escalate tension in eastern Ukraine.

He warned that "window to change course" was closing for Russia and that the U.S. was "ready to act" by imposing more sanctions on Moscow.