"We've made clear, there have been and there will be costs to Russia's action," White House Press Secretary Jay Carney told reporters at his daily news conference.
"We have a flexible tool in the executive order that the president signed that will allow us to calibrate the cost depending on the decisions that Russia makes, depending on whether or not Russia decides to avail itself of an opportunity here to pursue its concerns in Ukraine in a peaceful, diplomatic way," he said.
"This is part of our effort to work with our international partners and allies and to speak in a clear voice together that the actions taken by Russia to intervene militarily in contravention of international law and in violation of Ukraine's territorial integrity is something that we all oppose," he said.
"We are working to see if the Russians are willing to resolve this matter diplomatically. (The) Secretary (of State, John) Kerry has been in regular contact with (the Russian) Foreign Minister (Sergei) Lavrov. They spoke again today. And those conversations will continue," he said.
"We acknowledge that Russia has real interests in Ukraine, and deep historical, cultural, and economic ties to Ukraine. We believe that it is entirely appropriate and possible for Ukraine to integrate further with Europe, which is what so many Ukrainians desire, and even as it does so, maintain its very close and important relationship and ties to Russia," he said.
"The reports about lawlessness or abuse of Russian ethnic Ukrainians in eastern Ukraine have no credible foundation as far as we can say," he said.
"If the concern here is about the plight of ethnic Russians in Crimea or in other parts of Ukraine, there is a way to address that does not require the illegal mobilization of foreign troops or the illegal annexation of the sovereign territory of another state," Carney said.