Liberal Party leader Justin Trudeau confirmed he will be taking part in what's shaping up to be a massive climate march in Montreal Friday.

Trudeau made the announcement Thursday at a campaign stop in Sudbury, Ont.

"I look forward to marching with thousands of Canadians tomorrow in Montreal, "Trudeau said, "like people are marching right across the country and around the world to fight for the environment."

Tens of thousands of Montrealers - Montreal's mayor expects upward of 300,000 - many of them students, are expected to attend the march, which begins at noon Friday at the base of Mount Royal. Several schools have already announced they will be closed to allow students to attend the march.

Among those expected to attend is Greta Thunberg, the Swedish teen activist who has made international headlines with her efforts to raise awareness of climate change and its effects.

Among those who won't be in attendance is Quebec Premier Francois Legault, who has previously said he believes schools should remain open the day of the march.

In Montreal Thursday, Conservative Party leader Andrew Scheer said he won't be at the march either, but that his party would be represented.

The march is expected to bring many of the city's streets to a standstill.

Metro and commuter train services, as well as Bixi bike sharing services, will be free to use Friday.