Russian airline Aeroflot on Sunday violated a ban on aircraft from the country using Canadian airspace, regulator Transport Canada said, on the same day the restriction was imposed in response to Moscow's invasion of Ukraine.
"We are aware that Aeroflot Flight 111 violated the prohibition put in place earlier today on Russian flights using Canadian airspace," Transport Canada said in a tweet late on Sunday.
Flight 111 travels from Miami, Florida to Moscow and took off at 15:12 ET, according to FlightRadar24.
There are no direct flights between Russia and Canada, but several Russian flights a day have until now passed through Canadian airspace to other countries, a spokesperson for Transport Minister Omar Alghabra said.
Transport Canada said it will launch a review into the conduct of Aeroflot and Canada's air-traffic control service provider Nav Canada following the violation.
"We will not hesitate to take appropriate enforcement action and other measures to prevent future violations", the Canadian regulator said.
Nav Canada confirmed to Reuters that Aeroflot did enter the Canadian airspace. It said the aircraft operator declared the flight as a humanitarian flight as it entered the domestic airspace which requires special handling by air traffic control under normal circumstances.
"We are currently cooperating with Transport Canada to investigate the occurrence, and are working with neighbouring Air Navigation Service Providers to support rerouting of aircraft prior to them entering Canadian-controlled airspace," Nav Canada said.
Aeroflot did not immediately respond to Reuters' requests for comment.
Minister Alghabra announced at 0900 ET on Sunday that Canada would close its airspace to Russian aircraft operators following similar measures from other countries.
"We will hold Russia accountable for its unprovoked attacks against Ukraine," transport minister Alghabra wrote in a Twitter post.
Britain has banned Aeroflot from entering British airspace. Poland and the Czech Republic also said they were banning Russian airlines from their airspace, while airlines including IAG-owned British Airways and Virgin Atlantic began routing flights around Russian airspace.
Canada has imposed severe sanctions on Russia, targeting Russian President Vladimir Putin and Foreign Minister Sergei Lavrov in tandem with the United States.
Canada was also part of a Western alliance that blocked "selected" Russian banks from the SWIFT payments system on Saturday.