Ontario's finance minister says he will be looking "very closely" at British Columbia's tax aimed at foreign homebuyers as he looks for ways to address eroding affordability in Toronto's housing market.

Charles Sousa says he welcomes the 15 per cent tax that the B.C. government will charge foreign nationals looking to snap up homes in Vancouver's scorching real estate market.

Sousa says he is part of a committee, alongside Federal Finance Minister Bill Morneau and B.C. Finance Minister Mike de Jong, that's looking for ways to improve housing affordability in Canada's hottest markets.

He says it's important to consider that any policies introduced to cool down Toronto's hot real estate sector could have effects on other parts of the province that aren't seeing the same problem.

BMO chief economist Douglas Porter has urged the Ontario government to follow B.C.'s move, given that single detached houses in the Greater Toronto Area have jumped almost 20 per cent year-over-year.