At a news conference in the Dutch capital, the prime minister became animated when discussing Russia's sanctions earlier this week against several Canadian politicians and officials, as well as Paul Grod, the head of the Ukrainian Canadian Congress.
"They did not merely sanction a bunch of elected people," Harper said at the conclusion of the Nuclear Security Summit.
"They sanctioned a man for the sole reason that he's Ukrainian. Now what does that tell you about the mentality of that government? What does it tell you about the reasons why Ukrainians fear so much the Russian relationship with their country?"
He also questioned the regime's "mentality" in response to a Russian official's remarks to the Globe and Mail that Canada should stay out of Moscow's affairs, given it's located so far away from eastern Europe.
"There's a lot said about the mentality in that, that you would say that because something is far away, that you have no concerns about people's rights, or their lives or the basic principles of international law," he said. "I think that says a lot."
Canada, in fact, has every right to condemn Russia's aggression in Ukraine, including its formal annexation of Crimea a week ago, the prime minister said,
"I agree we've been outspoken; I think part of the reason is the kinship we have with a million Ukrainian-Canadians. They're all our friends and neighbours. I grew up with Ukrainian Canadians — they were some of my best friends — so we understand a bit about the history, a bit about what's at stake here."
Harper's comments came the day after the G7 effectively booted Russia out of the G8. Russian officials, meantime, said Tuesday they hoped to maintain contact with their G8 partners.
U.S. President Barack Obama and his G7 allies agreed to stand down on harsher economic sanctions against Moscow unless it dares to seize even more territory in eastern Europe amid the biggest crisis in the region since the Cold War.
During his own news conference at the end of the summit — a meeting woefully overshadowed by the Ukrainian crisis — Obama said no military force would be used to remove Russia from Crimea.
But he added the annexation of the strategic Black Sea peninsula was not a "done deal." Harper, in fact, has called for a "complete reversal" of Moscow's actions in Crimea.
"It is up to Russia to act responsibly and show itself once again to be willing to abide by international norms," Obama said. "If it fails to do so, there will be some costs."
Harper begins a two-day visit to Germany on Wednesday. He is to meet German Chancellor Angela Merkel, who, along with Harper, is senior among the G7 leaders.
The two have a close relationship. They chatted amiably, and almost exclusively, as they posed Tuesday for a group photo at the nuclear summit.
"I've always had a good relationship with Chancellor Merkel," Harper said. "We've lived through a range of crises and economic ups and downs and a few political ups and downs as well."
The Germans, along with other European nations, were initially hesitant to impose tough economic sanctions on Russia, given that they do so much trade with the Russians and depend on the country's oil and gas.
But in recent weeks, Merkel has shifted to the more strident North American stance, reportedly infuriated by Putin's false assurances to her last month that he had no designs on Crimea.
Harper said he would reassure Merkel that Canada could help the Germans out in the event it faces an energy shortage if the West decides to target Russia's lucrative energy sector.
"There's economic opportunity for Canada; obviously it's our intention in any case to do what we can to try to export energy outside the North American continent," he said.
"But that all said, we are looking at programs of sanctions. We all believe that in the short run, this is going to cause us all, including (Canada), some pain as well."
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