Ukrainian authorities launched an “anti-terrorist” campaign Sunday against pro-Russian gunmen and Ukrainian officials are suspicious that Russia is involved.
"I think we've seen that the sanctions can bite. And if actions like the kind that we've seen over the last few days continue, you're going to see a ramping up of those sanctions," Power said.
Sen. John McCain (R-Ariz.) said the United States should shore up Ukraine's armaments in the ongoing crisis.
"We ought to at least, for God's sake, give them some light weapons with which to defend themselves," McCain said on CBS's "Face The Nation." He added that some in the Ukrainian government "feel abandoned" by the United States.
Vice President Biden plans to travel to Kiev later this month, the White House announced Saturday.
Questioned on reports about a recent poison gas attack in Syria, Power said the U.S. is trying to confirm what happened.
"We are trying to run this down. So far, it's unsubstantiated. But we've shown, I think in the past, that we will do everything in our power to establish what has happened and then consider possible steps in response," she said.