The junior defence minister now is saying the government is looking at all options to replace the air force's aging CF-18 fighter-bombers.
Earlier this week, Associate Defence Minister Julian Fantino told a parliamentary committee the government has not ruled out abandoning the troubled project altogether. On Friday, Fantino told a gathering of defence industry representatives the only thing that is not up in the air at the moment is the amount of money the Tories are willing to spend on new jets.
"All options are on the table," Fantino said.
"We will manage the replacement of the CF-18 in a responsible fashion, and in a way that safeguards taxpayers' dollars."
The Conservatives have set aside $9 billion to replace the CF-18s.
Fantino, the minister in charge of buying military equipment, said the government has the flexibility to move up or back in the line to buy the new aircraft, or buy more or fewer than the planned 65 planes. He added that no contracts have been signed yet and no orders have been placed.
Harper echoed Fantino's comments in Montreal on Friday.
"We haven't signed a contract and that's just a fact," the prime minister said. "As I've said, the Canadian government — not just our government, the previous government — has been participating in the development of replacement aircraft for the CF-18 for 15 years.
"The reason that route was chosen was to not just work with our allies, but to obviously maximize the benefits for our industry in the development of new aircraft. ... But obviously at some point the planes will reach the end of their useful life. At some point we'll have to make a final decision, but obviously we have not signed a contract, so that we can retain our flexibility in terms of ensuring the best deal for taxpayers."
The Conservatives say they still believe the high-tech jet is the best choice to replace the CF-18. But they have softened their political rhetoric of late over the country's most costly military purchase.
A few months ago, Fantino was professing his unwavering support for the F-35s 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."
Compare that to this week, when Fantino told the House of Commons defence committee: "We have not, as yet, discounted the possibility, of course, of backing out of any of the program."
Such talk was a non-starter in Tory circles a year ago.
"I do find it disappointing, I find it sad, that some in Parliament are backtracking on the F-35 and some are talking openly about cancelling the contract, should they get the chance," Harper said on Jan. 14, 2011, at the Heroux-Devtek plant in Dorval, Que.
"Cancelling a contract that way would be completely irresponsible. The opposition parties must stop playing partisan games with these crucial contracts."
Critics pounced Friday on Fantino's change of tone.
"We've been raising questions in the House of Commons for months on the F-35s in terms of the replacement of aircraft for the military, and so what is really damning to the government is the fact that they've been misleading in their answers to Parliament for months on end," Liberal MP Wayne Easter said after question period.
"Yes, they may be coming around to saying there's other options on the table and admitting to the fact that the numbers that they’ve been putting out there are not what they have claimed them to be.
"That may be a little bit reassuring, but what is really damning to the government is how they've handled this F-35 boondoggle from beginning to end, where in fact they have been not up-front and honest and transparent with Parliament in terms of their answers."
"Our Canadian Forces have come forward and first told the minister we need 80 planes to replace the CF-18 fleet," New Democrat MP Matthew Kellway said.
"Then they've come forward and said 65 at a minimum. And so how many planes this minister can actually purchase for nine billion, I don't know. He doesn't know. ... We should be very clear before we decide what we're going to do, how many planes we need and what price they're going to cost."
The purchase price in any given year depends on how many other countries are placing orders.
The price tag has been the subject of furious debate in Parliament, with the Conservative government insisting it will pay roughly US $75 million per aircraft when it starts buying in 2016. Critics say the figure is low.
The U.S. and Britain signed contracts for the delivery of early-production aircraft at between US $140 million and $145 million each. Canadian officials have long insisted that the price will drop as the assembly line ramps up.
"I'm often asked why our budget for replacing our CF-18s has not increased, even as the estimated current costs of the F-35, before it reaches full production, has failed to decline as rapidly as predicted," Fantino said.
"The answer is simple: we have been prudent and responsible in our budgeting, and will continue to be so."
The price tag for the jets could determine how many Canada orders. But the junior defence minister wouldn't hazard a guess about how many jets will be bought.
"I'm not going to speculate. I'm going to tell you again that we have a $9-billion envelope," Fantino told reporters after a speech at a defence industry gathering.
"I've tried to explain what that means in terms of contingency that we have built in there. We're going to do the best we can with that amount to ensure that our men and women have the best equipment.
"So, numbers are off the table right now, other than the only one I can tell you for certain is the $9 billion."
The first of the new F-35s would not be delivered until sometime between 2017 and 2023.
— With files from Andy Blatchford in Montreal
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