President Obama calls for international monitors in Ukraine, says Russia's actions violate international law.
The House has approved a $1 billion loan guarantee package for Ukraine, as part of the U.S. effort to support the new government as Russia continues to occupy the Crimean Peninsula.
Top Republicans say they'll support economic sanctions against Russia as punishment for aggression in Ukraine.
President Obama and Secretary of State John Kerry push back on Russia's actions in Ukraine.
The Russian military has given Ukrainian forces in Crimea until 5 a.m. Tuesday (10 p.m. ET Monday) to surrender or face a "storm," Interfax news agency reported.
Russia appears to be ignoring the U.S. and its allies request to stay out of the Ukraine.
Large numbers of Russian troops were reported landing at a military air base in Crimea Friday, prompting Ukraine to accuse Russia of a military invasion.
President Viktor Yanukovych signed a deal with Ukraine's main opposition leaders on Friday brokered to end the deadly violence that put the country on the brink of civil war.
More bloodshed occurred in Ukraine Tuesday despite a truce called by the government and opposition.
President Obama says Ukrainian government will be held responsible for deadly clashes as he arrives for summit in Mexico.