Buying a fighter jet that's different from the one used by Canada's closest allies risks disconnecting the country from the global alliances it needs the most, a former Conservative defence minister said Monday.

Peter MacKay told a Senate committee that in his mind, there's no question the F-35 is the right plane for Canada — from defending the Far North to helping to confront the threat of terrorism around the world.

MacKay's government tried to purchase that very plane but questions about its costs and capabilities forced a halt to the process — something MacKay said he regrets.

"I'm very much lamenting some of the to-ing and fro-ing that's going on currently over the purchase of fighter aircraft," he said.

"Do I regret that we did not make the final purchase of that aircraft? Absolutely. We need it, it's good for industry, it's good for interoperability, we need it at Norad."

Canada's participation in the F-35 joint strike fighter jet program has been in question since Justin Trudeau announced during the last election campaign he would not approve the purchase of the jets. (U.S. Air Force/Reuters)

During the election campaign, the Liberals said they would not buy the F-35 and would instead open the process up to a competition. However, cabinet is now grappling with how to meet that commitment and Canada's defence needs at the same time.

Outside the hearing, MacKay said some of the problems that dogged Lockheed Martin's F-35 at the early stages of the process have been fixed. It is not just being flown by the Americans, but several other countries, he noted.

"The F-35 is by far the superior aircraft," he said.

"It is by far the one that brings the most industrial benefits to Canada, it's proven its value time and time again, they've got the bugs out, countries are taking delivery of it now, the cost is coming down.

"Its superiority is proven and we need it and we need it soon, so having a competition — if that's what they need to justify it, then fine, then keep your word, just do it."

The former Chrétien Liberal government kick-started the process of replacing Canada's CF-18s in 1997. The Conservatives took up the process when they formed government in 2006.

David Pratt, who served as a Liberal minister of defence in 2003-04 under former prime minister Paul Martin, told the committee the Conservatives had 10 years but still failed to get the job done.

"We need an open competition in order to ensure that we're getting the best plane for Canada — now."