Affordable housing has yet to make a big impact on the federal election, but Vancouver Mayor Gregor Robertson wants party leaders to make "clear" commitments to address what he calls a "real problem" in Canada.

In an appearance on CTV's Power Play, Robertson said big cities across the country are facing a "crunch" to address homelessness as well as the rising costs of homes and rental properties.

"There are tens of thousands of people homeless in Canada -- we have a $7-billion cost of homelessness in our country," said Robertson.

"And we have millions of people affected by the lack of affordable rental housing across Canada."

Robertson said the housing crisis is not only a drain on people's wallets, but the country's economy as a whole.

"You have working people in cities across Canada who can't afford to live close to where they work, and they can't take transit to somewhere they can afford into their workplace," said Robertson.

The Vancouver mayor was in Toronto on Thursday at a meeting of the Federation of Canadian Municipalities' Big City Mayor's Caucus to rally up support on the issue.

Robertson said he was gearing up to "push" federal leaders to make "very specific" commitments to address the affordable housing crunch during the last few weeks of the campaign.

"There are so many people affected by it that you think it would be an important political issue," said Robertson.

"The next government of Canada has to deal with it."

Robertson said he plans to deliver his message by attending candidate forums and other local meetings over the next couple weeks.

"We're going to be putting pressure on the federal candidates who are competing for seats in our cities making sure they come forward with their commitments … (and) obviously this rolls up to the federal leaders," said Robertson.

The Vancouver mayor said he has seen some "some good promises" so far, but stopped short of endorsing a federal leader.

"Not just yet," said Robertson.

Case in point: Robertson commended the Liberal Party for its $20-billion commitment to social infrastructure, but said it was too vague.

"We don’t know specifically what is going to affordable housing and homelessness," said Robertson.

The Liberals have also promised to eliminate the GST on all new rental builds and provide $125 million a year to landlords for renovations to aging homes.

At last week's leader's debate, Liberal Leader Justin Trudeau committed to "restoring" the long-form census to see if issues such as foreign-home ownership merit further consideration.

Robertson also said the NDP have made some "solid commitments" but he wants to see "more specifics and bigger numbers to address the crisis that we have."

The NDP has said it would raise money for affordable housing using measures such as the corporate income tax.

Meanwhile, the Green party has committed to creating a national housing strategy and freeing up funding for co-operative housing.

Unlike his rivals, Conservative Leader Stephen Harper denied that the country was facing a housing crisis at the Globe and Mail debate last week.

"In Canada we have seen home ownership rise to record levels … because people have been able to take care of low interest rates when their job prospects have been solid and good, and their incomes have been growing," said Harper.

With files from The Canadian Press