TORONTO (Reuters) - Sales of existing homes in Canada climbed to the highest level since April 2010 in January, led by strong markets in Vancouver and Toronto, the Canadian Real Estate Association (CREA) said on Tuesday.

More than half of the local markets surveyed by CREA posted gains from the month before with a total of 39,481 homes sold in January, up 4.5 percent from 37,773 in December. Sales were down 6.6 percent from January 2010, however.

Sales may have risen because of the federal government's announcement last month that it will tighten mortgage rules, CREA said. The new rules start coming into effect on March 18.

"If last year can be used as any guide, sales activity may heat up further as we get closer to the date on which tighter mortgage regulations come into effect, especially in some of Canada's pricier markets," said Georges Pahud, CREA's president.

Canada's most expensive markets recorded strong sales gains in January. Toronto sales rose 4.9 percent, while Vancouver posted a 14.2 percent gain.

CREA said the national average price in January was C$343,675 ($347,146), little changed from the past three months. But it was up 4.5 percent from a year earlier, partly because of a jump in the number of multimillion-dollar homes sold in the Greater Vancouver area, CREA said.