Nearly half of Canadians want to deport people who are illegally crossing into Canada from the United States, and a similar number disapprove of how Prime Minister Justin Trudeau is handling the influx, according to a Reuters/Ipsos opinion poll released on Monday.

A significant minority, four out of 10 respondents, said the border crossers could make Canada "less safe," underlining the potential political risk for Trudeau's Liberal government.

The increasing flow of hundreds of asylum-seekers of African and Middle Eastern origin from the United States in recent months has become a contentious issue in Canada.

There has been broad bipartisan support for high levels of legal immigration for decades in Canada. But Trudeau has come under pressure over the flow of the illegal migrants.

A group of refugee claimants, from Eritrea, cross the border from New York into Canada, earlier this month in Hemmingford, Que. (Ryan Remiorz/Canadian Press)

He is questioned about it every time he appears in Parliament, from opponents on the left, who want more asylum-seekers to be allowed in, and critics on the right, who say the migrants pose a potential security risk.

Canadians appeared to be just as concerned about illegal immigration as their American neighbours, according to the poll, which was conducted between March 8-9. Some 48 per cent of Canadians said they supported "increasing the deportation of people living in Canada illegally."

When asked specifically about the recent border crossings from the United States, the same number — 48 per cent — said Canada should "send these migrants back to the U.S." Another 36 per cent said Canada should "accept these migrants" and let them seek refugee status.

Refugees are much more welcomed when we have gone and selected them ourselves as a country, as opposed to refugees who have chosen us. - Janet Dench , Canadian Council for Refugees

In the United States, where President Donald Trump was elected partly on his promise to boost deportations, 50 per cent of adults supported "increasing the deportation of illegal immigrants," according to a separate Reuters/Ipsos poll that was conducted during the same week in the United States.

Illegal migrants interviewed by Reuters in Canada said they had been living legally in the United States and had applied for asylum there. But they had fled to Canada for fear of being caught up in Trump's immigration crackdown.

Kellie Leitch, a prominent contender to be leader of the official opposition right-leaning Conservative Party, said the opinion poll results reinforced her belief that Canadians did not want Ottawa to accept the asylum-seekers.

"I am happy to see that my position on illegal border crossers ... has support from the public," she said in an email.

Warming weather poses risk

In the poll, support for deporting the border crossers was strongest among men, adults who do not have a college degree, people who are older and those with higher levels of income.

"There are so many people in the world who want to come in and go through the right channels," said Greg Janzen, the reeve of Emerson, a Manitoba town near the U.S. border, which has seen hundreds of border crossers.

"That's what's pissing most people off. These guys are jumping the border," he said.

Forty-six per cent of Canadians feel the influx would have no effect on safety, while 41 per cent said it would make Canada less safe, according to the poll.

"Refugees are much more welcomed when we have gone and selected them ourselves as a country, as opposed to refugees who have chosen us," said Janet Dench, executive director of Canadian Council for Refugees.

Asylum seekers walk during a cold night along railroad tracks in Canada, after crossing from the U.S. (Jill Coubrough/CBC)

Of those polled, 46 per cent disagreed with how Trudeau was handling the situation, 37 per cent agreed, while 17 per cent did not know. In January, a separate Ipsos poll found that 59 per cent of Canadians approved of Trudeau, while 41 per cent disapproved.

Trudeau faces no immediate threat, since the next elections are not until 2019. Trudeau's office declined to comment on the poll.

Brian Lee Crowley, head of the Macdonald-Laurier Institute public policy think-tank, said the number of illegal migrants could spike as the weather warms, and "if people become convinced there's a large uncontrolled flow of illegal immigrants, I think that will be a very serious political issue for the government."

Canadian authorities dismiss the idea they are being lax.

Dan Brien, a spokesman for Public Safety Minister Ralph Goodale, said "trying to slip across the border in an irregular manner is not a 'free' ticket to Canada," noting that all asylum-seekers were detained.

"If they are found to be inadmissible without a valid claim, deportation procedures are begun," he said when asked about the poll.

Those who cannot be identified, are a flight risk or pose a public danger can be detained, he added.

According to a separate Ipsos poll in Canada, 23 per cent of Canadians listed immigration control as among the top national issues in March, up from 17 per cent in December. It ranks behind healthcare, taxes, unemployment and poverty as top concerns.

The Canadian government set an immigration target of 300,000 for 2017, or just under one per cent of the population, the same level as 2016. It reduced the 2017 target for resettled refugees to 25,000 from 44,800 in 2016, a year when it welcomed 25,000 refugees from Syria.

The Reuters/Ipsos poll was conducted online in English and French throughout Canada. It included responses from 1,001 people who were at least 18 years old. Individual responses were weighted according to the latest population estimates in Canada, so that the results reflect the entire population.

The poll has a credibility interval, a measure of accuracy, of four percentage points.