Another red flag has emerged in Calgary's real estate market, with the Canada Mortgage and Housing Corporation now saying there's "strong overall evidence" of "problematic conditions" in the city.

Regina, Saskatoon and Toronto also shared the "strong" rating in the CMHC's latest Housing Market Assessment report, released Wednesday.

The previous report, issued three months earlier, found weak overall evidence of problems in Calgary's housing market.

CMHC economist Bob Dugan said evidence of overbuilding has increased since the previous assessment in Calgary and this could lead to lower prices.

"In some cases, a correction in housing prices may be required in order to ensure excess supply is absorbed so balance in the market can be restored," he said.

Edmonton, Winnipeg, Ottawa, Montreal and Quebec City had "moderate" overall ratings, while every other major city was rated as "weak" in the report, which looks at the first quarter of 2016.

The CMHC report said low oil prices are affecting Alberta and Saskatchewan, in particular, by "weakening demographic and economic fundamentals such as migration, employment and income, which are in turn affecting housing markets."

CMHC developed the quarterly assessments in an attempt to to detect "problematic housing market conditions" before they potentially lead to major market events "such as the house price bubble Toronto experienced in the late 1980s and early 1990s," according to the report.

Here is the full report: