Torontonians looking up this morning have been met with a confusing sight: a plane with a "Sorry Toronto" banner flying over the city.

In a bout of wishful thinking, some hoped that it was Toronto's public transit service apologizing for a delay-ridden morning commute.

Turns out, it's part of a new campaign from Tourism Montreal called Sorry, apologizing to Toronto in advance for all the noise the city is expected to make during Montreal's 375th birthday celebrations, which run through 2017.

Along with the banner, a video was released of Montrealers knocking on doors in Toronto and handing out tickets for free trips to Montreal.

Montreal's 375th birthday is set to be feted with a wide array of projects and events, such as a new downtown skating rink and a light installation added to the Jacques Cartier Bridge. The city has set aside $329 million for capital works projects for the anniversary.

If you thought Toronto was confused, just wait: the "sorry" campaign will visit New York in 2017.