Obama cautions Congress not to increase sanctions against Russia without European agreement.
The Ukrainian president asked Congress Thursday to provide more assistance, including military equipment.
He also demanded that Putin take immediate action to ensure open access for international investigators to the crash site of Malaysia Air Flight 17.
US and its G-7 allies will impose new sanctions against Russia as soon as Monday, the White House said.
Said Putin wants to restore the Soviet Union.
"It’s a country that certainly needs a revision of the constitution that would include a mechanism where the regions would be heard and their views would be taken on board," Sergey Kislyak says on ABC's "This Week."
President Obama says there's no new Cold War; Americans aren't as optimistic.
Package expected to provide Ukraine with $1 billion in loan guarantees and about $150 million in direct U.S. assistance.
"But in terms of who's playing politically against America, of course it’s Russia."
Senate leaders spar over Ukraine aid as the House and Senate continued debating competing bills Tuesday with no signs of resolution.