Following many weeks of tension between Russia and Ukraine, new developments have pushed the two Eastern European countries to the brink of war.

The ousting of pro-Russian president Yanukovich and his subsequent exile to Russia has prompted the latter to reassert control over the region, claiming to defend the Russian minority in Ukraine as well as its geopolitical assets.

During the week, there were reports of Russian troops taking control over airports in Sevastopol, where the Russian Black Sea Fleet is stationed, and Simferopol, Crimea's regional capital. However, according to CNN, Russia's ambassador to the UN claimed these to be false rumors. 

On Saturday, Reuters reports that the Russian Federation Council approved President Vladimir Putin's request to intervene in Ukraine with a unanimous vote of 90-0. Putin's argument for force was "in connection with the extraordinary situation in Ukraine, the threat to the lives of citizens of the Russian Federation, our compatriots" and to protect the Black Sea Fleet in Crimea.

The occupation of Crimea was hailed by the Russian majority in the province as well as in many eastern cities. Still, the new Ukrainian government does not approve of the invasion.

"Ukraine will not be provoked," newly-elected Prime Minister Arseniy Yatsenyuk said. "We will not use force. We demand that the government of the Russian Federation immediately withdraw its troops and return to their home bases."

Other world leaders, including President Obama, have stated their discontent with the Russian intervention.

"It would be a clear violation of Russia's commitment to respect the independence and sovereignty and borders of Ukraine, and of international laws," President Obama said in a statement on Friday. "...And indeed, the United States will stand with the international community in affirming that there will be costs for any military intervention in Ukraine."

The Los Angeles Times reports that Russian involvement already could be affecting Ukraine's fragile cohesion. While armed men occupied the regional parliament in the Crimea, a new government was elected that is pro-Russian under Sergei Aksenov. He called for Russian intervention to stabilize the Crimea.