MOSCOW - Russia and Ukraine have been locked in an exchange of accusations over responsibility for a crashed Malaysia Airlines passenger plane - believed shot down by pro-Russia rebels in the border area. As the war of words continues, analysts say pressure on Russia will only grow.
Emergency workers and investigators are combing through fields in eastern Ukraine near the rebel-controlled crash site where nearly 300 people died.
Despite having downed Ukrainian military aircraft, pro-Russia rebels deny responsibility for the Malaysian crash, and are turning over evidence to Moscow.
Ukraine's Prime Minister Arseny Yatseniuk called for an international investigation for what he called a "crime against humanity."
"Let me express on behalf of the Ukrainian government my deep condolences to those innocent, who were killed by Russian-led terrorists, " said Yatseniuk.
Ukraine and western governments accuse Moscow of supplying heavy weapons to the militias to keep the region destabilized.
Russia rejects the accusation and President Vladimir Putin is blaming the air crash on Ukraine for fighting the rebels.
"In relation to this I would like to mention that this tragedy would not have happened if there was peace in that land, if the fighting had not been restarted in the south-east of Ukraine. And of course, the state on whose territory this happened carries the responsibility for this terrible tragedy," said Putin.
The scale of the disaster could prove a turning point for international pressure to resolve the crisis in Ukraine.
While the West has imposed sanctions on Russia over Ukraine, the United States has been more aggressive than the European Union. Analysts say the response of Germany and other EU powers to the incident - possibly imposing more sanctions - could be crucial in deciding the next phase of the standoff with Moscow.
Political commentator Konstantin von Eggert says that more sanctions are inevitable.
"I think there will be more sanctions. Because, I don't think that Russia, even if it wanted to, can pull out of this Ukrainian quagmire quite soon," said von Eggert.
But analyst James Nixey, of the British policy institute Chatham House, believes that while the West will continue to apply pressure with possible further sanctions, Putin has his own strategy.
"There is in fact a new Russian toolbox for dealing with disagreements in the post-Soviet space and by extension, the West. And that toolbox includes a number of weaponry, if you like. And that weaponry can be actual weaponry - tanks, as in Crimea - but can also be in terms of bribery or coercion or energy cut offs or diplomacy even. So there are instruments that Putin can use - benign and illegitimate - in order to achieve his goals," said Nixey.
NIxey says this so-called toolbox will likely deter the West from escalating beyond applying tougher sanctions.