Canada is home to a pretty large Lebanese community and for the last 6 months, they've been pushing Air Canada to offer direct flights between Beirut and Montreal.
However it's not up to the airline, they need approval from the Canadian Government first. And according to The961, the route had been cancelled due to security reasons.
A petition was launched to get the ban reversed but this was the response from The Government of Canada
"The safety and security of Canadian passengers is a top priority. The Government of Canada is aware that there is demand for direct flights between Canada and Lebanon and of the interest in providing such a service. Today, travellers can fly between Canada and Lebanon and book their flights with a single airline; however, passengers have to take a connecting flight operated by another airline, usually in Europe. When Transport Canada considers new flight routes, there are many factors that are considered by it and other key departments beyond aviation safety and security, which include national security, international relations, economic considerations and facilitation of passenger travel. At this time, direct flights between Canada and Lebanon remain prohibited for national security reasons."