Both the NDP and Liberals said scenes of desperation playing out overseas make it clear the federal government must do something to aid the thousands of people flocking to the Continent, although they offered no new policy proposals.
"Hundreds of thousands of people fleeing horrors: We've got to step up to the plate, we've got to be part of an international solution, we've got to start doing our fair share," NDP Leader Tom Mulcair said.
"Mr. Harper has failed completely so far to do just that."
Justin Trudeau repeated his party's position that Canada would, under a Liberal government, take in 25,000 Syrian refugees.
He also accused the Conservative government of not living up to its "meagre" commitment to accept refugees from Syria and elsewhere.
"We need to provide the support we can, and we need to be making this situation better in various ways that, quite frankly, we're not doing at this time," Trudeau said.
Conservative Leader Stephen Harper, who has committed during the campaign to allow 10,000 more Middle East refugees into the country over the next four years, said Wednesday that simply granting asylum to the desperate won't fix the crisis.
"We have plans to do more, but I would say repeatedly that as we are doing more, we can't lose sight of the fact that refugee resettlement alone cannot, in any part of the world, solve this problem," Harper said.
The extremist Islamic State of Iraq and the Levant is at the root of the problem, he said.
The Conservative government promised in January to accept 10,000 refugees from Syria over the next three years. But it came under criticism after refusing for weeks to release information on how many had arrived.
Days after the campaign began last month, the Citizenship and Immigration Department said that as of late July 1,002 people had resettled in Canada as part of the January commitment.
For months, the 28-member European Union has been at odds on how to cope with the tide of more than 332,000 refugees who have arrived at its borders this year. Greece, Italy and Hungary have pleaded for more help. Germany, which is expecting to receive an EU-leading 800,000 asylum seekers this year, has appealed for EU partners to bear more of the load.
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