OTTAWA -- Defence Minister Harjit Sajjan says he's looking at all options when it comes to finding 18 fighter jets to bridge Canada into a new fleet to replace its aging CF-18 Hornets.

Sajjan announced last fall that Canada was entering talks to buy 18 Boeing Super Hornets to cover a "capability gap" created when the government changed how it counts the number of planes the country needs to fill its NATO and NORAD obligations.

But Boeing this spring initiated a U.S. Commerce Department complaint against Canadian aircraft manufacturer Bombardier, leading Foreign Affairs Minister Chrystia Freeland to say in an open letter that Canada is reconsidering its Boeing procurement.

The trade dispute has raised questions about how the government will handle its fighter jet procurement.

In an interview with Evan Solomon, host of CTV's Question Period, Sajjan wouldn't rule out purchasing Lockheed Martin's F-35 fighter jets as an interim solution, in addition to considering it among the possibilities to fully replace the current fleet.

"Right now we are looking at many different options," Sajjan said.

"Keep in mind this all just happened. It does take time to … be able to develop some various options," he added.

"We are committed to making sure that we have this capability gap filled."

Tom Lawson, Canada's former chief of the defence staff, says the fact the government's new defence policy review said very little about fighter jets suggests "a retrenchment on a wrongheaded policy." The policy review said Canada would increase the number of jets it will buy, from 65 to 88.

"There really is no one except the government that believes that 18 interim fighters will be useful to Canada, let alone the RCAF [Royal Canadian Air Force],” Lawson told Solomon.

"This conflict that's going on with Boeing right now regarding the Bombardier issue provides them an opportunity to gracefully step back from that and go right to the competition [for the permanent fighter jet]."

Lawson, a long-time supporter of the F-35, has provided paid advice to Lockheed Martin since retiring from the Canadian Forces. His support for the F-35 dates back to his time as assistant chief of the Royal Canadian Air Force.

Richard Fadden, a former deputy minister in the Department of National Defence, says he has always argued Canada should buy the F-35.

"One of the most important components of our military policy is we have to be interoperable," Fadden said.

"The F-35 has been purchased by a large number of allies. I think the government should try and find a way to accept that and move forward with the F-35s."