Putin's behavior sign of failing Ukraine invasion: Canada's Trudeau

Russia-Ukraine War: "Putin's behavior only goes to show that his invasion is failing," Canadian Prime Minister Justin Trudeau said.

Russian President Vladimir Putin's military mobilization order and threats to use nuclear weapons show that the Ukraine invasion is failing, Canadian Prime Minister Justin Trudeau said on Wednesday, condemning Moscow's announcement as unacceptable.

Russia-Ukraine War: Canadian Prime Minister Justin Trudeau speaks to the media. (AFP)

"Canada condemns Putin's irresponsible escalation of the war, his partial military mobilization, his nuclear threats, as well as Russia's rushed referendums to try to annex parts of Ukraine are unacceptable," Trudeau told reporters in New York, where he is attending the United Nations General Assembly.

"Putin's behavior only goes to show that his invasion is failing," Trudeau said.

In a televised address earlier on Wednesday, Putin announced Russia's first wartime mobilization since World War Two and plans to annex parts of Ukraine. He also threatened to use nuclear weapons to defend Russia, declaring: "It's not a bluff".

Moscow calls its actions in Ukraine a "special military operation" to "disarm" its neighbor and root out dangerous nationalists. The West says it is a land grab and an attempt to reconquer a country that broke free of Moscow's rule with the break-up of the Soviet Union in 1991.

Putin's speech followed mounting casualties and battlefield setbacks for Russian forces, who have been driven from areas they had captured in northeast Ukraine in a Ukrainian counter-offensive this month and are bogged down in the south.

Trudeau said the threats of nuclear weapons need to be taken seriously and Western allies need to "stand very firmly against" them.

Canada would continue to support Kyiv by strengthening its sanctions on Russia and sending military aid to Ukraine, he said.