OTTAWA -- U.S. and Canadian fighter jets have intercepted and escorted two Russian reconnaissance planes flying off the coast of Alaska, only days after Canada's top general described Russia as the greatest immediate threat to North America.

Canadian CF-18s and American F-22s were scrambled Monday after the North American Aerospace Defence Command spotted the two Russian Tu-142 Bear aircraft approaching the Alaskan coast, Norad said in a statement.

The Russians remained in international airspace over the Beaufort Sea north of Alaska for about four hours before departing, according to Norad. They approached within 50 nautical miles, or 92 kilometres, of the Alaskan coast, but did not enter U.S. or Canadian airspace.

The Tu-142 is a long-range maritime reconnaissance and anti-submarine aircraft, though one version of the plane can be used to communicate with Russian ballistic submarines.

"Norad continues to operate in the Arctic across multiple domains," U.S. Gen. Terrence O'Shaughnessy, Norad commander, said in a statement. "As we continue to conduct exercises and operations in the North, we are driven by a single unyielding priority: defending the homelands."

The appearance of Russian aircraft off North America's coast comes less than a week after Canadian military officials, including chief of the defence staff Gen. Jonathan Vance, called Russia the greatest military threat to North America today.

"The most immediate state-sponsored military threat, if I could caveat it that way, that we face right now and today in physical space is Russia. I would say that China poses a more credible threat in cyberspace right now," Vance told a defence conference in Ottawa on March 4.

The Russian flight also comes as the federal government is preparing to launch a major review of North America's defences, including those that go beyond the traditional domains of land, sea and air to include space, cyberspace and information.

The Liberal government has said it plans to upgrade those defences alongside the U.S., though it has not set a timetable or budget for the initiative.

This report by The Canadian Press was first published March 10, 2020.