President Barack Obama warned on Monday that Russia was 'on the wrong side of history' on Ukraine, referencing the 'strong condemnation' from countries around the world to bolster his statement.

Speaking in the Oval Office, Obama said Russia's intervention violated both Ukraine's sovereignty and international law.

The statement comes amid conflicting reports about an ultimatum from Russia to Ukraine's navy forces in Crimea to surrender. Ukraine's navy headquarters in Sevastopol say they've been given a deadline of 10 p.m. ET Monday to surrender or face military assault. Russia denies these claims.

On Tuesday, NATO will convene for the second time in a 48-hour period on the Ukraine crisis and U.S. Secretary of State John Kerry will travel to Kiev.

Click on the map above to see the position of various countries and statements of world leaders on Russia's intervention.