Montreal air authorities say they're keeping a close eye on competition emerging south of the border from a new international airport in Plattsburgh, N.Y.

The airport, scheduled to open June 1 complete with bilingual signs and a French website, hopes to attract Canadian travellers from Montreal and Quebec heading to U.S. destinations.

Montreal airport authority president James Cherry said there's no doubt the new Plattsburgh hub will be able to offer cheaper landing fees and lower taxes on plane tickets, discounts that will entice Canadian travellers to choose it as a port of departure.

It's a phenomenon many Canadian airports near the U.S. border have to confront. "Toronto has the same issue with Buffalo, Vancouver has the same issue with Bellingham. It's not unique to our situation," Cherry told CBC.

The Trudeau airport can't slash prices because it pays high taxes, as all Canadian airports do, he added. "About 35 per cent of our costs are in one form or another a transfer to a government, either in the form of property taxes to the city of Montreal, or rent that we pay on our airport to the federal government."

Montreal authorities are more concerned about the new airport's effect on other hubs in the metropolitan region. "We see it as a potential threat to cargo traffic and to commercial development," Cherry said.

The St. Hubert airport south of Montreal has already taken steps to protect its business with Pratt & Whitney Canada, an international aircraft engine manufacturer.

Airport officials have asked the federal government for a $70 million investment to renovate its facilities in a bid to secure Pratt & Whitney Canada's expansion plan over Plattsburgh.

Pratt & Whitney officials have refused to comment on rumours that it plans to move part of its operations to the New York state airport.

With files from the Canadian Press