U.S. officials tell CNN there's more evidence of a Russian troop buildup along the border with Ukraine, and there is evidence that the Russia is targeting Ukrainian military positions.
The State Department also says Russia is getting ready to deliver heavier and more powerful rocket launchers to separatist forces in the Ukraine.
Retired Air Force General Michael Hayden, former director of the Central Intelligence Agency and the National Security Agency, is OutFront.
The chorus of people accusing Russia of playing a partial role in the rocket attack that killed 298 people on board Malaysia Airlines Flight 17 is growing louder.
The Russian president, though, remains defiant.
CNN's Kyung Lah has more OutFront in Ukraine.
Vice President Joe Biden is in Ukraine, where he delivered some strong words to Russia's Vladimir Putin.
Biden said "no nation has the right to simply grab land from another nation" and urged Russia to stop supporting the masked militants in eastern Ukraine.
Secretary of State John Kerry weighed in too, threatening sanctions will be imposed by the U.S. absent any measurable progress to de-escalate the tension.
But are sanctions and tough talk enough?
Jason Carroll is Outfront with a look at how some of America's biggest food chains are hoping to turn Russia's economic uncertainty into profits.
Outfront tonight with more insight on the showdown between the U.S. and Russia is journalist and author Carl Bernstein – who is also a CNN contributor – and Stephen Cohen, Professor Emeritus of Russian Studies at NYU and Princeton University and also the author of a cover story for The Nation this week called "Media Malpractice: Putin, Sochi and Ukraine."
Here to discuss Putin's mentality and what the U.S. can do to sway him is former U.S. Navy intelligence officer Colonel Cedric Leighton and author Keith Darden, who wrote "Resisting Occupation in Eurasia."