THE HAGUE, The Netherlands — “Is it a crime to be a Ukrainian?” Prime Minister Stephen Harper demanded to know Tuesday as he loudly denounced Russian President Vladimir Putin for barring Paul Grod of the Ukrainian Canadian Congress from entering Russia.

“Putin has decided to censure the leader of the Ukrainian community in Canada. What did he do?” the prime minister asked. “That indicates the mentality of Putin’s government; their lack of respect, not only for Ukraine as a country, but also of Ukrainians as members of a real nation.

“This is fundamental. It demonstrates why Ukrainians are so resistant to the relationship between Russia and their country.”

Grod was the only non-parliamentarian or senior government adviser on a list of 13 Canadians that Russia barred from visiting on Monday after Canada declared about as many Russian officials and close associates of Putin “persona non grata” because Russia had annexed the Crimean peninsula from Ukraine last week.

Harper made the remarks at the end of a two-day Nuclear Security Summit and an emergency meeting of the Group of Seven industrialized nations at which it was decided to indefinitely suspend Russia from the Group of Eight over the sudden seizure of the Crimea.

With such summits largely taking place out of public view, divining how influential or persuasive any leader is with his colleagues can be a mug’s game. But it is clear that several weeks of fiery rhetoric from Harper, during which he often personalized the crisis by condemning Putin by name, has made him a leader on the Crimean file and contributed to a stronger than expected response from the G7.

Harper’s Cold War style in Holland contrasted sharply with Obama’s. In a rambling, wishy-washy answer to a question on Ukraine, the president ignored the realities created by Russia’s intervention in Crimea, saying there was enough space for Ukraine to be a friend with both the West and Russia.

The prime minister’s week in Europe, which ends with Germany on Wednesday and Thursday, began Saturday with a brief, symbolic tour of Kyiv. It was the first visit to Ukraine by a western leader since Viktor Yanukovych’s regime got overthrown in a bloody street coup last month and Russia responded to the departure of its ally by swallowing the Crimean peninsula.

With only six hours on the ground in the Ukrainian capital there was hardly any time for Harper to learn about the tumult that has seized that country for the past few months. But it was enough to give Harper some “street cred” with his G7 colleagues when they sat down to consider how to try to slow Putin and his army down.

As well as agreeing Tuesday to boycott a G8 summit that Russia had been scheduled to host this June, the G7 decided that if Putin sends troops to invade the Ukrainian mainland much tougher targeted sanctions against entire sectors of the Russian economy such as the energy industry would follow.

It was “conceivable” that sanctions against Russia’s energy sector might eventually create some benefit for Canada’s energy industry, but even without the Crimean crisis, his government’s policy had been to promote energy exports, Harper said.