Concerns over Ukraine's financial condition mounted this week after Russian state gas company Gazprom said it was cancelling a substantial discount on natural gas granted to the former satellite country in December. Putin, meanwhile, noted Ukraine still owes some $2 billion for gas.
Clinton told a business audience on Thursday that Putin's incursion in Ukraine follows a pattern of behaviour he established with the invasion of Georgia in 2008.
"Vladimir Putin cherishes a vision of a greater Russia. His goal is to re-Sovietize Russia," Clinton said to the 2,500 who came to hear her speak in Calgary.
"That means trouble. And that's why everyone is scrambling to prop up Ukraine ... and to try to prevent future escalation."
Russia's position on Ukraine's gas debts is a shift from last year, when Moscow tolerated letting the country pile up unpaid bills. The change in tone came following the ouster of Ukraine's pro-Russian President Viktor Yanukovych by protesters who want closer ties with the European Union.
"One of the principle tools of intimidation that Russia has used is their energy resources — both in the winter of 2006 and then on Jan. 1, 2009, when the giant Russian energy company Gazprom shut off all natural gas exports to Ukraine," Clinton said.
"That was a wake-up call and it sent a chill, not only across Ukraine, but indeed across Europe. There are cases when one nation tries to use its energy supply to dominate or intimidate another. Russia's behaviour toward Ukraine is an obvious example."
Clinton warned that the West's role in the Ukrainian crisis has reached a delicate point, because Russia is at a crossroads and must decide if it will work with the West to create a better economic future.
"If Putin were not so fixated on reclaiming the Soviet empire and crushing all signs of dissent, he might realize that Russia's hand in dealing with extremists along Russia's southern plain as well as a potential rivalry to the east with China (would) be strengthened," Clinton said.
"Unfortunately as it stands, Russia under Putin remains frozen between a past it can't let go of and a future it can't bring itself to embrace."
Clinton also criticized Russia's reopening of old Soviet military bases in the Arctic.
"It's not only Ukraine and Georgia we're now keeping our eye on," she said.
"It does threaten to militarize that pristine region that both Canada and the United States have interests in, to preserve the Arctic and help to develop it in a sensible manner."
Clinton said it is in the best interests of Russia, Canada, the United States and the five other Arctic Council members to find ways to reach agreements on how to handle resource development in the Arctic, which "is clearly coming."
Canada's formal scientific submission to the United Nations has claimed 1.2 million square kilometres of seabed under the Atlantic. It has also made a preliminary claim in the Arctic Ocean and hopes to expand Canada's Arctic claim to include the North Pole.
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