US won't recognize Crimea annexation
Crimean officials have called a vote for next Sunday to confirm that the region, which has an ethnic Russian majority, is a part of Russia in the wake of the ouster of Ukraine's Moscow-allied president last month.
Blinken, US President Barack Obama's deputy national security adviser, said on CNN's "State of the Union" program that Russia would come under increased international pressure as a result of the referendum in Crimea.
"First, if there is an annexation of Crimea, a referendum that moves Crimea from Ukraine to Russia, we won't recognize it, nor will most of the world," Blinken said.
"Second, the pressure that we've already exerted in coordination with our partners and allies will go up. The president made it very clear in announcing our sanctions, as did the Europeans the other day, that this is the first step and we've put in place a very flexible and very tough mechanism to increase the pressure, to increase the sanctions."
Obama will meet with Ukrainian Prime Minister Arseny Yatseniuk at the White House on Wednesday to discuss a resolution to the Crimea situation.
Obama has said a referendum on Crimea would violate international law and the Ukrainian constitution. Last week he announced sanctions including travel bans and freezing of assets of individuals responsible for Russia's military intervention in Crimea. Russian President Vladimir Putin was not among the individuals.