Secretary of State John Kerry challenged Russian President Vladimir Putin on Wednesday to "prove by his actions not just his words that he is committed to peace" in Ukraine. The comments came one day after Putin instructed the Russian parliament to repeal a law allowing Moscow to order a military intervention in Ukraine. Kerry told a news conference held after a NATO meeting in Brussels that while he was "delighted" at the move, "this could be reversed in 10 minutes and everyone knows that."

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Kerry said he wanted to see the Russian leader instruct rebels to lay down their arms and free military observers still captive in eastern Ukraine. "Until Russia makes that kind of commitment, the United States and Europe will prepare greater costs, including sanctions, in the hope they won't be used," he said. Hours into an agreed ceasefire between Ukraine's government and rebels, militants shot down a helicopter killing nine people. "This was shot down with a Russian weapon, a MANPAD [a shoulder-launched surface-to-air missile]," Kerry said.