"We have not, as yet, discounted the possibility, of course, of backing out of any of the program," Julian Fantino, associate defence minister, told the House of Commons defence committee Tuesday.
Fantino made the comment after a series of pointed questions from the opposition parties.
A tiny shift in the hard-headed policy on the country's most costly military purchase, it is also a drastic departure from the political rhetoric of a few months ago when Fantino declared his unwavering support before an American business audience.
"We will purchase the F-35," the minister was quoted on Nov. 8 in Fort Worth, Tex., home of the Lockheed Martin plant that builds the jets.
"We're on record. We're part of the crusade. We’re not backing down."
The Conservatives say they still believe the high-tech jet is the best choice to replace the aging CF-18s, but the minister suggested Tuesday they are taking a cautious approach.
"We're going to, at some point in time, make the definitive decision," he said. "We have not, as of yet, signed a contract to purchase."
None of the other nine allied nations have given up the option of bailing on the program, and Fantino said Canada won't either.
Outside the committee, Fantino denied that the government is climbing down from its support for the jet.
"I'm being realistic," he said.
"Until such time as the purchase is signed and ready to go, I think the only appropriate answer for me is to be forthright. We are committed to the program.
"We intend to do the best we can for our men and women and Canadian taxpayers with respect to replacing the CF-18s."
Fantino insisted the government will not leave the air force in the lurch as the current fleet of 1980s-vintage CF-18s reach the end of their projected service life around 2020.
"And we'll just have to think it through as time goes on."
New Democrat critics have been relentless in the Commons by tag-teaming questions every day.
"We knew this project was shaky and now today we see a complete about-face," said defence critic David Christopherson, who pointed out the Conservatives have launched scathing attacks on critics.
"It's all bluster. The reason they suggest someone is unpatriotic is because they don't have solid answers to give. They need to be accountable to Canadians for the action they take."
The Liberals, who used the eye-popping F-35 price tag as one of the justifications for defeating Stephen Harper's minority government last year, were more low-key, but equally keen to watch the government squirm.
Defence critic John McKay described the testimony as "a welcome change in tone" that was evidently brought on by a meeting earlier this month in Washington where partner nations had a chance to quiz both the manufacturer and the Pentagon, which is co-ordinating international orders.
"My question is: How come it took so long? We've been saying this for years."
Since declaring their intention to go with F-35, the Conservatives have doggedly defended the decision. They've dismissed calls for a reconsideration of the project and attacked critics who question the uncertain price tag.
The Harper government says the $9 billion it intends to spend on 65 of the jets is carved in stone. But the government won't see a firm price until it gets close to first delivery, which is nominally expected in 2016.
The cost for 20 years' of in-service support remains a matter of debate, with the air force insisting it will only run in the neighbourhood of an additional $7 billion — a figure the Parliamentary Budget Officer disputes.
Even Pentagon estimates suggest the maintenance bill could run between US$14 billion and US$19 billion.
In months of questioning in the Commons, Fantino has insisted there is no need for a backup plan in case of further delays in the project as the manufacturer works out software and design glitches.
On Tuesday, he told the committee he was waiting for defence officials to prepare alternate scenarios to the F-35 deal, the so-called Plan B that opposition parties have demanded.
He described the request as "what if" research.
Dan Ross, the senior defence official in charge of procurement, testified that his staff and the air force have been continuously monitoring the international aircraft market, but played down the idea that there is a lot of choice available.
"We don't see a change in what's out there," Ross said.
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