U.S. President Barack Obama announced the "most comprehensive" set of sanctions against Russia since the Cold War during a speech at the White House on Monday, one day after citizens of Crimea voted to leave Ukraine for Russia. The President said he was ready to impose additional measures should Russia move to annex the Ukrainian peninsula.
See also: Under the Gun, Crimea Votes Overwhelmingly to Secede From Ukraine
The U.S. slapped sanctions on several individuals either involved in or with ties to the Russian government and the nation's arms sector, including an aide and adviser to Russian President Vladimir Putin, as well as leaders in Crimea's autonomous government.
President's says Russia is only isolating and hurting itself; threatens future measures against Moscow, which depend on Putin's actions — West Wing Reports (@WestWingReport) March 17, 2014
See also: Crimea Votes: The Day in Pictures
"If Russia continues to interfere with Ukraine, we stand ready to impose further sanctions." Obama said in his statement from the James S. Brady Press Briefing Room. He added, "We'll continue to make clear to Russia that further provocations will achieve nothing except to further isolate Russia and diminish its place in the world. The international community will continue to stand together to oppose any violations of Ukrainian sovereignty and territorial integrity, and continued Russian military intervention in Ukraine will only deepen Russian isolation and exact a greater toll on the Russian economy."
Tension between Russia and Western nations have escalated since Russian troops invaded the Ukrainian peninsula of Crimea in the beginning of March. Russia claims it is protecting ethnic Russians from Ukrainian rioters who ousted former President Viktor Yanukovych from office, but the majority of Western countries see the invasion as a violation of international law.
Crimea held a referendum on March 16 to decide whether to become a part of Russia, an event that the West has decried as illegal. Voters overwhelmingly chose to become part of the Russian federation, but the ballot left them little choice. There were just two options, one which favored joining Russia, the other which favored greater independence. There was no option to remain with Ukraine.
Seven U.S. senators who recently returned from a visit with Ukraine's newest government decried the vote as a sham.
I lost the bet. A shameless 95% in #Crimea "referendum" - just like the old days in the Soviet Union
— John McCain (@SenJohnMcCain) March 16, 2014
 
Reminder as Crimean ppl vote on Russian referendum while occupied & under threat of force: sham process won't be recognized by US. #Ukraine
— Senator Dick Durbin (@SenatorDurbin) March 15, 2014
The U.S. has already placed sanctions on Sergey Aksyonov, the pro-Russia leader of Crimea as well as Sergey Glazyev, and has doled out measures against 11 individuals so far. European Union foreign ministers froze the assets of 21 Russian and Ukrainian officials on Monday who they believe are linked to perceived illegal actions in Ukraine.
Obama said that his government's response going forward will depend on what Russia decides to do next.
"We can calibrate our response based on whether Russia chooses to escalate or deescalate the situation," Obama said. "I believe there is still a path to resolve this diplomatically in a way that addresses the interests both of Russia and Ukraine."
NATO also vowed to cooperate more closely with Ukraine after the Crimean vote. Ukraine's Foreign Minister Andriy Deshchytsya flew to NATO headquarters in Brussels, Belgium on Monday to request equipment needed to deal with Crimea's potential secession. It's not clear what Deshchytsya may have asked for.
To the president, the path to resolution includes Russia moving troops back to bases within its own country, more international monitors to assess the progress of Ukraine's new government and engaging in a dialogue with that government as it moves toward elections.
"We're going to stand firm in our unwavering support for Ukraine," Obama said.
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