Story highlights Russian defense minister says Malaysia Airlines Flight 17 crash was Ukraine's fault

Ukrainian and Russian Presidents are satisfied by ceasefire, official says

Petro Poroshenko: "This is another hope that peaceful initiatives have a good perspective"

Moscow has repeatedly denied sending Russian troops into Ukraine

Some 70% of the Russian troops believed to have been in Ukraine have withdrawn back across the border, Ukrainian President Petro Poroshenko said, according to the national news agency Ukrinform.

"This is another hope that peaceful initiatives have a good perspective," Poroshenko is quoted as saying during a Cabinet meeting in Kiev on Wednesday.

The remarks came several days into a shaky ceasefire deal between Ukrainian forces and pro-Russia rebels, signed last Friday after nearly five months of fighting in eastern Ukraine.

The Presidents of Russia and Ukraine are "broadly satisfied" with the status of the ceasefire, a Kremlin aide said Wednesday.

President Vladimir Putin and Poroshenko spoke by phone Tuesday night, Kremlin foreign policy adviser Yuri Ushakov told Russia's Interfax news agency.

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"On the whole, satisfaction was expressed on our part and by the Ukrainian side with how the ceasefire is being observed although it is a difficult process," Ushakov said.

Moscow has repeatedly denied allegations by Kiev and the West that it is sending Russian troops over the border into Ukraine.

Meanwhile, EU leaders are weighing whether to pull the trigger on tougher sanctions against Russia.

Talks are planned Thursday in Brussels among diplomats from the 28 member nations, following a decision Monday to put on hold for at least a "few days" a new package of economic penalties against Russia over its encroachment in Ukraine.

The delay offered more time to assess the effectiveness of the ceasefire without risking further trade retaliation by the Kremlin, which has said it will respond if new sanctions come into force.

OSCE to deploy drones

The chairman of the Organization for Security and Cooperation in Europe, which is monitoring the truce, said Wednesday that more observers would be sent to eastern Ukraine.

"Around 70 specialists are in the Donetsk and Luhansk regions this week already to monitor the ceasefire. Further monitors are being recruited and deployed as we speak," Didier Burkhalter said.

The OSCE will be using its own drones over the region soon, he said. A discussion is also under way on the possible deployment of drones from some of the 57 member states of the OSCE.

Burkhalter, who is also the Swiss President and Foreign Minister, said his country was ready to support the OSCE mission in Ukraine with up to 10 additional monitors and an extra 500,000 euros ($647,000.)

MH17 crash report

Russian Defense Minister Sergey Shoigu blamed Ukraine for the crash of Malaysia Airlines Flight 17 in comments Wednesday after meeting with Malaysian Defense Minister Hishammuddin Hussein in Moscow, Russia's state-run Itar-Tass new agency reported.

"The catastrophe happened in the skies of Ukraine, which is fully responsible for what happened," Shoigu is quoted as saying.

"I'm convinced that this tragedy wouldn't have happened if Ukraine had solved its internal crisis without use of military force, including artillery, missiles, and war aviation."

A preliminary report into the crash in July, released by Dutch aviation investigators Tuesday, said the plane was brought down by "high energy objects" from outside.

The U.S. and Ukraine have accused pro-Russian separatists operating in the region of downing the plane, which had 298 people on board, using a Russian-made missile system.

The report supports the theory of a warhead exploding in close proximity to the passenger jet, but it doesn't point any fingers at who might have fired it.