HALIFAX -- Defence Minister Harjit Sajjan says Russia's disruptive behaviour on the world stage is a key concern for Canada.

Sajjan made the remark Friday at the opening of the Halifax International Security Forum, a three-day event that has attracted security experts and politicians from around the world.

The minister cited Russia's annexation of Crimea and its aggressive posture toward neighbouring Georgia as examples of a worrisome trend.

"The disruptive nature that Russia has taken, it goes against the rules-based order that we're used to," he told a news conference at a downtown hotel.

He said the recent commemorations marking the 100th anniversary of the end of the First World War serve as a poignant reminder of the fragility of democratic institutions.

"It's even more important now that nations act in a responsible manner; that we do not provoke," he said.

"Unfortunately, because of the actions that Russia has taken, we do need to make sure we send a strong message of deterrence, and with NATO we are doing that."

Canada has taken a particular interest in confronting Russia's use of so-called hybrid warfare, which blends conventional warfare and cyber-warfare to destabilize democracies, Sajjan said.

Peter Van Praagh, president of the Halifax International Security Forum, said Russia's internal struggles have had an impact on the rest of the world.

"Russia is a great country historically, but Russia is also a failing country, simultaneously," Van Praagh told reporters.

"Russia is struggling with both of those things going on at the same time."

On Saturday, a panel of experts will take part in a discussion titled: "Beijing's Cravings, Kremlin's Gremlins: Freedom's Foes."

"Russia doesn't have the same advanced tools that Canada and NATO has," Van Praagh said. "Russia is using different tools to exert influence ... We can't allow Russia or any other country to interfere in the operations of domestic democracies."

The conference, which has attracted 300 delegates from 70 countries, is being held in conjunction with a meeting of the NATO Parliamentary Assembly.

Van Praagh also cited the end of the First World War 100 years ago, saying delegates to the conference will be keeping that key event in mind.

"Looking at 1918 through the prism of 100 years is a good reminder of the cost of war," he said. "It is also a reminder of our responsibility to protect our democracy. The work of democracy is never quite complete."

It's the fourth time Sajjan has attended the security conference as defence minister.

He said other key issues that require delegates' attention include the conflicts in Syria and Yemen, ongoing political changes on the Korean peninsula and Canada's renewed role as an international peacekeeper.

"For a decade, (the forum) has been the place to discuss global defence and security issues that define our times," he said.

Among those invited to speak at the forum is U.S. Gen. Joseph Dunford, chairman of the Joint Chiefs of Staff. Dunford is the highest-ranking military officer in the United States and an adviser to President Donald Trump.

The delegates to the forum are almost exclusively from democratic regimes.