The borough of Ville-Marie is going to require bars and restaurants in downtown Montreal to install ashtrays outside their establishments.

Borough Mayor Benoit Labonté says the accumulation of cigarette butts has been "staggering" since a ban on smoking in public buildings took effect three weeks ago.

"There's 600,000 people coming every day [to] downtown Montreal. Let's say one-third of them smoke twice a day — only twice a day — outside," Labonté calculates. "If you add this, it's three million cigarette butts every week on the public domain, so there's a problem there."

Montreal Mayor Gérald Tremblay launched an appeal to his citizens when the Tobacco Act was first enforced on May 31. "I would like to repeat my appeal to restaurant and bar owners to install outdoor ashtrays for their customers," he said.

But the Ville-Marie borough council is going a step further, and will bring in the ashtray bylaw next week, Labonté said.

Labonté says he doesn't anticipate much opposition from bar and restaurant owners.

Pressure for the ashtray bylaw came from merchants, Labonté said.

Regulations would give owners until the end of the summer to complete the installations.