The Russian parliament's upper chamber voted on Wednesday to revoke the right that it had granted President Vladimir Putin in March to order a military intervention in Ukraine, where Kiev is struggling to quell a rebellion by Russian speakers in the east.
Justifying the move, which Putin had requested, a senior lawmaker said it should be seen as an act of goodwill to help facilitate peace efforts in Ukraine, but that the Federation Council stood ready to reinstate the authority if needed.
The vote was carried by 153 votes in favor to one against.
This comes after President Vladimir Putin asked Russia's upper house on Tuesday to revoke the right it had granted him to order a military intervention in Ukraine in defense of Russian-speakers there.
Minutes before he spoke, Kiev said pro-Russian rebels in east Ukraine had shot down a military helicopter, most likely killing all nine on board. It was the most serious breach of a temporary ceasefire agreed in talks between government and rebels less than 24 hours earlier.
Putin's move received a cautious welcome in the West as a sign Moscow was ready to help engineer a settlement in Ukraine's largely Russian-speaking east, where a pro-Russian uprising against Kiev began in April.
Ukrainian President Petro Poroshenko called it a "first practical step" following Putin's statement of support last weekend for Poroshenko's peace plan for eastern Ukraine.
But later he told security chiefs to "open fire without hesitation" if government forces came under attack, and "did not rule out bringing the ceasefire regime to an early end" if rebels continued to breach it, his press service said.
Putin himself said he now expected Ukraine to begin talks on guaranteeing the rights of its Russian-speaking minority, which Russia would continue to defend.
Sanctions
The United States is working with its European partners to prepare a new round of sanctions against Russia in case they are necessary, U.S. Secretary of State John Kerry said on Wednesday.
"We are not announcing a new round of sanctions today but we are going to continue to take steps to prepare in the event that the circumstances on the ground warrant those sanctions. So, we are coordinating with our European partners in order to prepare for that."
Earlier, a spokeswoman for EU Foreign Policy Chief Catherine Ashton declined comment when asked whether Putin's step would reduce the likelihood of tougher sanctions being agreed at an EU summit in Brussels on Friday.
The White House welcomed Putin's backing for the ceasefire, but said there must be "tangible actions" to defuse the crisis.
President Barack Obama spoke with British Prime Minister David Cameron and agreed that the United States and the European Union would "work to implement additional coordinated measures to impose costs on Russia" if it failed to take immediate steps to de-escalate the situation in Ukraine, the White House said.
Even the limited sanctions already imposed by Washington and the EU have chilled investor sentiment in Russia at a time when its economy is already on the brink of recession.