By Mick Krever, CNN

The downing of MH17 was indeed a "game-changer" as many Western leaders have called it, Vladimir Chizhov, Russian ambassador to the EU, told CNN's Christiane Amanpour on Tuesday.

"I agree it's a game-changer," he said. "It should serve as a wake-up call for everybody to stop instigating violence, stop supporting the Ukrainian government in its military campaign against civilians."

In the past 24 hours, Russian President Vladimir Putin has taken tentative steps to quell the mounting public outrage over the botched recovery and investigation of the MH17 crash site in eastern Ukraine.

Nonetheless, Putin has said that in fact Ukraine is at least indirectly to blame for the downing of the civilian airplane, because, he alleges, of its continuing offensive against pro-Russian separatists.

"I think it's a time of decision for everybody, including those Western countries that have been supporting Ukraine," Chizhov said.

"If we talk about influence, I think influence on the Kiev government side from the West should really increase. As far as Russia's influence on the people in eastern Ukraine, you can easily see that from public statements made by President Putin over the last few days."

Putin today promised to use his sway on the separatists.

"I can assure that it is in the national interests of Russia to see this conflict end as soon as possible," Chizhov said. "And we never thought it would serve any interest to prolong it or exacerbate it."

Meanwhile, the ambassador said that no one had produced any convincing evidence that pro-Russian rebels, or indeed Russia, had a role in the attack.

Ukraine, he said, has concentrated on "producing fake evidence."

"In the meantime, the United States government has said that it has mounting evidence pointing to what they - to those whom they call rebels or separatists, but have yet to produce any piece, any tangible piece of evidence."

Meanwhile, Russian Army Lt. Gen. Andrei Kartapolov suggested a Ukrainian jet fighter might have shot the plane down.

Ukrainian President Petro Poroshenko rejected that in an exclusive interview with Amanpour, saying that all Ukrainian aircraft were on the ground at the time.

"The Russian Defense Ministry did not blame actually anybody. But it produced hard evidence showing that some questions need to be answered by the Ukrainian authorities, which they have failed to do so far."

"So in the lack of any other evidence which would point to the contrary, I think the strongest evidence so far is the one produced by the Russian minister of defense."

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