As Russia expands its influence in Syria and Europe, one of Russian President Vladimir Putin's most vocal critics is asking the Canadian government to move quickly to bring in stronger economic sanctions.

"We're in a new Cold War. What do you do in a cold war? You contain your enemy," American financier and human rights activist Bill Browder said in an interview with Rosemary Barton on CBC News Network's Power & Politics.

Browder is in Canada this week to hold the Liberal government to a campaign promise — the adoption of the Magnitsky Act, a series of economic sanctions and asset freezes against Russian officials responsible for the detainment, torture and 2009 death of Sergei Magnitsky, Browder's Russian lawyer who blew the whistle on a $230 million tax fraud by government officials.

"It's a no-brainer. It's very simple — should we or should we not allow Russian torturers and murderers to come to Canada?" said Browder, who was blacklisted himself by the Russian government in 2006 after 10 years of doing business in the country. 

Browder doesn't have a timeline from the government on when Canadians might expect the Magnitsky Act to be passed, but he's hopeful the government will act fast to enact the legislation, which was passed by the United States in 2012 and the European Parliament in 2014.

A March 2015 motion by former Liberal MP Irwin Cotler was unanimously passed by the House of Commons, but died  because of the federal election.

"This is my top priority for 2016," Browder said. "Government laws and government promises take a long time, and the devil's going to be in the details. The small print can make or break whether this is a useful and aggressive tool, or a non-tool."

'Sanctions are killing' Putin

The Kremlin critic is confident that economic sanctions are the best way to hit Putin where it hurts — his pocketbook.

"It's devastating to be on the sanctions list," he said. "You basically become a non-person. As a result of that, just the fear of being put on the list balances the scales a bit."

Canada has already imposed a series of economic sanctions on Russia for its aggression in Ukraine. But Browder wants to see Russian human rights abusers added to the list. 

Pulling no punches, Browder told Barton Russia's actions in Syria have changed the game, and made it all the more imperative for Western countries to punish Putin economically. 

"Russia's effectively a war criminal now," he said, adding that the country is acting "as a sort of rogue mafia state" with its bombing campaign in Syria and action in Ukraine. 

Engage with Russia, but with caution

But shutting down communication with Russia completely isn't the answer, said Browder.

"If engagement means the foreign minister of Canada should be talking with the foreign minister of Russia, fine. Let them talk," he said. 

"But if engagement means appeasement, begging Russia not to drop bombs in Syria or saying, could you please just be a little nicer in Ukraine, that's not going to work."

Browder had one piece of advice for Canada, gleaned from his own experience in Russia where he went from being a supporter of Putin to one of his biggest critics.

"The way Canada needs to deal with Russia is to understand that Putin is not a guy who understands anything other than power," he said. 

"If you have power over him, then he respects that."