MONTREAL -- The head of Syria's main Western-backed opposition group is pressing the Canadian government to do more to end the conflict in his home country.

George Sabra, president of the Syrian National Council, says the Syrian government's purported use of chemical weapons in recent days is another sign that a political solution isn't possible.

He wants Canada to offer more humanitarian aid and be a stronger international voice against Syrian President Bashar Assad.

"When we think about Canada, we think about human rights," Sabra said Saturday before a town-hall style meeting in Montreal.

"We expect a special role from Canada in this field."

Montreal was the first stop on Sabra's Canadian tour to meet with Syrian-Canadians and raise awareness about the situation in his home country. He is also scheduled to visit Toronto and Ottawa.

Sabra said he's planning to meet with Foreign Affairs Minister John Baird in the coming days.

Baird has maintained a political solution remains the best way to end the civil war in Syria, while at the same time pointing to what he calls "overwhelming" evidence of a chemical weapons attack against civilians in that country.

Baird's spokesman Rick Roth reiterated that line on Saturday, adding that Canada strongly supports the calls by the United Nations for a prompt investigation into allegations of chemical weapons use.

Meanwhile, Prime Minister Stephen Harper Harper had separate phone conversations Saturday with British Prime Minister David Cameron and French President Francois Hollande to discuss the situation.

Officials in the Prime Minister's Office say the three leaders shared their concern about the accusations that the government of President Bashar Assad used chemical weapons on civilians.

The Syrian government has denied using chemical weapons and has pointed the finger at rebel forces.