ROUGH CUT - NO REPORTER NARRATION
STORY: President Barack Obama said on Thursday that a proposed referendum in Crimea to join Russia would violate international law and said U.S. sanctions were aimed at punishing Moscow for its intervention in Ukraine.
"The proposed referendum on the future of Crimea would violate the Ukrainian constitution and violate international law," Obama told reporters at the White House.
"Any discussion about the future of Ukraine must include the legitimate government of Ukraine," he said.
