OTTAWA -- Reports of a Russian troop withdrawal from Syria could be good news for the country's desperate and suffering civilians searching for peace, Canada's immigration minister said Monday.

But John McCallum said it was too early to say whether the Russian announcement will prove to be positive.

"Anything that can heighten the odds of an end to the civil war, heighten the odds of a reduction in the literally millions of people displaced by this terrible war, anything that will do that is good," the minister said.

"Whether this will be a materially positive development or not remains to be seen."

Chantal Gagnon, a spokeswoman for Foreign Affairs Minister Stephane Dion, said Canada is following the situation closely "to see how Russia's intentions unfold. What remains critical is that a Syrian-led political transition is afforded the best chance at success."

Russian President Vladimir Putin has said he will pull some of his country's troops out of Syria.

The development raised hopes for success in the Syrian peace talks that began Monday in Geneva.

"I'm ordering the defence minister to start the pullout of the main part of our group of forces in Syria, beginning tomorrow," Putin said Monday on Russian television.

He didn't say how many troops would be withdrawn, nor is it known how many Russian military personnel are operating inside Syria.

The U.S. and Russia brokered a cease fire on Feb. 27 that has reduced the violence and has been mostly successful, even though there has been some periodic bloodshed.

On Tuesday, Syria will mark the fifth anniversary of the civil war that started with an uprising against Assad that has killed 250,000 and forced half the country's population to flee their homes.

"The Syrian situation looks desperate, which is why the world is facing the worst refugee crisis it has seen in decades and it is one of the main reasons why Canada has stepped up to the plate," McCallum said, referring to the Liberal government's decision to admit 25,000 Syrian refugees.

The minister said it would be "seven or eight months" before the government decides on the numbers of Syrian refugees it will admit in 2017.

"We will clearly, I think, have more refugees than was the case under the previous government. Whether we would have as many as this year remains to be seen, but this is part of the discussions we will be having going forward."

A report released Monday by the United Nations Children's Fund said one in three Syrian children, or 3.7 million, have been born into conflict after the outbreak of the civil war in 2011, including 151,000 children born as refugees.

"The thing about five years is that somebody who was in Grade 1 when the thing started would be in Grade 6. That's huge difference . . . it's half or more of a child's life," David Morley, the president of UNICEF Canada, said in an interview.

There are 2.1 million children inside Syria not going to school and another 700,000 in neighbouring countries, he said.

At least 40 schools were the targets of military attacks last year inside Syria, among the 6,000 schools in the country that are no longer usable, he said.

Younger children are being recruited by all sides as child soldiers, he said.

"It's breaking international humanitarian law. It's the same as attacking hospitals, attacking schools."

Putin also said Monday that the Russian airbase in Syria's coastal province of Latakia and a naval facility in the port of Tartus would remain operational.

Russia has conducted air strikes that the U.S. says have been aimed at keeping President Bashar Assad in power.

A coalition of humanitarian organizations in a report last week accused Russia of escalating the violence in Syria. It said Russian airstrikes had claimed the lives of 2,300 people in November alone.

"While the failure to end the terrible violence must primarily rest with those involved in the fighting, their international backers also have a responsibility to safeguard hope rather than fuel the fire," said Ann Witteveen, of Oxfam Canada.