Around 10,000 refugees will be brought to Canada by the end of the year, less than half of the 25,000 that was pledged by the prime minister.
Justin Trudeau, sworn in this month, made the initial pledge as part of his election campaign, but his critics said the goal was unrealistic.
Some provincial and municipal leaders have also complained the short timeline did not allow for enough security checks.
Others said they could not cope with such a heavy flow of new arrivals.
"We just looked at the logistics, we looked at what it would take to bring them in by January 1, and we had options around that," Trudeau told the Canadian Broadcasting Corp.
"We realised that we wanted to make sure that it was done absolutely right."
The government will fly in 10,000 refugees by the end of the year and the remainder by the end of February.
"We want to bring them fast, but we also want to do it right," John McCallum, Canadian immigration minister, said.
"If it takes a little bit longer to do it right, then take the extra time."
Some opinion polls, conducted in the wake of the deadly Paris attacks, have depicted the public's concerns about welcoming the big number so quickly.
There have also been several racist incidents involving the Muslim community in Canada.
In addition, support agencies have said that they will need extra funding, but they are ready for the influx once the refugees start arriving.
Syrians refugees are scheduled to start arriving via chartered aircraft early next month.
Of those, 40 percent will be sponsored by individuals and community groups, and the rest by the government.
Source: Al Jazeera and agencies