Obama Promises to 'Deepen and Broaden' Sanctions Against Russia

"Big countries can't just stomp on little countries," he says.

“The U.S. and Europe are finalizing measures to deepen and broaden our sanctions across Russia’s banking, energy, and defense sectors," he said.

Obama announced that all NATO allies will provide security assistance to Ukraine, including support and care for Ukrainian troops. Obama reiterated that pro-Russian separatists must keep their commitments, even as European leaders plan to intensify sanctions against the Russian government and its economy.

To apply pressure, Obama said the discussion at NATO and the international community's support of Ukraine has been "a testimony to how seriously people take the basic principle that big countries can't just stomp on little countries."

Obama’s comments come two days after he referred to the Russian advance in Ukraine as a “moment of testing” for the world, a problem that “challenges that most basic of principles of our international system, that borders cannot be redrawn at the barrel of a gun.”

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The usual strain in Russian-American relations was taken to an even more international stage this week after Obama visited Estonia in part to reassure the Baltic nations that America’s interests are also theirs, that Russian encroachments on sovereign nations would not evade the attention of Western nations.

“An attack on one is an attack on all, and so if, in such a moment, you ever ask again, ‘Who’ll come to help?’ you’ll know the answer: the NATO alliance, including the armed forces of the United States of America,” he told a gathering of almost 2,000 Estonians.

On Friday, Obama wasn't shy in taking partial credit for the ceasefire, telling reporters, "I'm very pleased with the kind of work that's been done throughout this crisis in Ukraine, and I think U.S. leadership has been critical throughout that process."