OTTAWA - The minister in charge of buying equipment for the military says there is no comparison between what Norway and Canada will pay for the F-35 stealth fighter.
Julian Fantino, the associate defence minister, told a House of Commons committee Thursday that "each country has its own separate and distinct formula" for calculating how much they'll spend on each aircraft.
The opposition New Democrats pointed out earlier this week that Norway estimates it will spend $40 billion for 52 of the radar-evading fighters — considerably more than the $16 billion the Harper government says it will spend for 65 jets.
Fantino says the Norwegians are asking that the F-35 be able to fire different kinds of weapons and he suggested those considerations are driving up the cost for that country.
Norway and Canada are purchasing the same base model of stealth fighter — known as the F-35A. It is capable of taking off from standard runways, unlike the two other variants meant for aircraft carriers and short runways.
Both countries have similar needs and have collaborated on modifications, including the installation of a drag chute to help slow the planes on icy northern runways.
The Norwegians have asked the U.S. manufacturer, Lockheed Martin, to include both software and structural modifications that would allow the F-35 to fire anti-ship weapons, known as a Naval Strike Missile.
It's unclear whether that would account for the huge price difference, especially since Australia is splitting the cost of the conversion with the Scandinavian country.
Fantino says it's very difficult to compare the purchases "dollar-for-dollar," but promised the all-party committee he would provide a more detailed explanation a some later date.
Chris Alexander, the parliamentary secretary to the defence minister, says the Commons committee will soon launch a study on the defence of North America and that the F-35 will figure prominently.
Opposition MPs on the committee were not swayed by Fantino's argument. They're demanding to see a straight-up, detailed comparison of the Canadian and Norwegian purchases, but defence officials objected by saying much of the information the Liberals and NDP want to see belongs in confidence to Norway.
"We don't know exactly what the Norwegians have purchased," deputy defence minister Robert Fonberg told the committee.
"There are base aircraft, with a purchase series of options and spares and a lot of other things for that aircraft. I don't think it would be appropriate for us to be speculating on exactly what the Norwegians have purchased as opposed to what we know we have purchased."
Liberal MP Frank Valeriote said it's clear "we don't know whether they are apples and oranges" being compared. Until that analysis is done, said Valeriote, nobody can rely on Fantino's explanation.
The parliamentary budget officer earlier this year accused the Conservatives of low-balling how much National Defence will spend on the controversial replacement for the aging CF-18s.
Kevin Page said the bill to taxpayers over the three decades the F-35 aircraft is expected to be in service is more like $30 billion, a figure the government has gone to great lengths to discredit.
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F-35 Joint Strike Fighter
FIIn this file photo taken on July 14, 2011 and released by U.S. Air Force, a USAF F-35 Lightning II joint strike fighter (JSF) aircraft soars over Destin, Fla., before landing at its new home at Eglin Air Force Base. Japan selected the Lockheed Martin F-35 stealth fighter Tuesday, Dec. 20, 2011, to replace aging jets in its air force and bolster its defense capability amid regional uncertainty. (AP Photo/U.S. Air Force, Staff Sgt. Joely Santiago)
F-35 Joint Strike Fighter
A F-35 Lightning II sits on stage during the United Kingdom F-35 Lightning II delivery ceremony on July 19, 2012 at Lockheed Martin Corporation in Fort Worth, Texas. The ceremony marked the first international delivery of an F-35 Joint Strike Fighter to a partner nation. (Photo by Tom Pennington/Getty Images)
F-35 Joint Strike Fighter
(Photo by Brendan Smialowski/Getty Images)
F-35 Joint Strike Fighter
Plane models stand outside the Lockheed Martin Corporation during the United Kingdom F-35 Lightning II Delivery Ceremony on July 19, 2012 in Fort Worth, Texas. The ceremony marked the first international delivery of an F-35 Joint Strike Fighter to a partner nation. (Photo by Tom Pennington/Getty Images)
F-35 Joint Strike Fighter
The F-35 Joint Strike Fighter jet sits in front the entrance of the Asian Aerospace 2004 show in Singapore 24 February 2004. The Asia Pacific offers one of the world's strongest prospects for defence-related spending, US aerospace giant Lockheed Martin said Tuesday as it expressed confidence in remaining a major supplier to the region's governments (AFP PHOTO/ROSLAN RAHMAN)
F-35 Joint Strike Fighter
(AFP PHOTO/CARL DE SOUZA)
F-35 Joint Strike Fighter
A Lockheed Martin's F-35 Lighning II fighter jet sits on the tarmac for static display at the Singapore Airshow in Singapore on February 12, 2012. Boeing's much-delayed 787 Dreamliner is set to star at the Singapore Airshow this week where companies touting private jets and defence hardware to the Asian market will also be out in force. (ROSLAN RAHMAN/AFP/Getty Images)
F-35 Joint Strike Fighter
(ROSLAN RAHMAN/AFP/Getty Images)
F35 JSF Take Off
F-35A Flight with External Stores
On Feb. 16, 2012, the first external weapons test mission was flown by an F-35A conventional takeoff and landing (CTOL) aircraft at Edwards Air Force Base, Calif. The F-35A is designed to carry up to 18000 pounds on 10 weapon stations featuring four weapon stations inside two weapon bays, for maximum stealth capability, and an additional three weapon stations on each wing.
F-35 Joint Strike Fighter
IN AIR, NAVAL AIR STATION PATUXENT RIVER, MD - FEBRUARY 11: (EDITORS NOTE: Image has been received by U.S. Military prior to transmission) In this image released by the U.S. Navy courtesy of Lockheed Martin, the U.S. Navy variant of the F-35 Joint Strike Fighter, the F-35C, conducts a test flight February 11, 2011 over the Chesapeake Bay. Lt. Cmdr. Eric 'Magic' Buus flew the F-35C for two hours, checking instruments that will measure structural loads on the airframe during flight maneuvers. The F-35C is distinct from the F-35A and F-35B variants with larger wing surfaces and reinforced landing gear for greater control when operating in the demanding carrier take-off and landing environment. (Photo by U.S. Navy photo courtesy Lockheed Martin via Getty Images)
F-35 First Ship Landing
Courtesy: NAVAIR/JSF Program/Lockheed Martin
F35 Hovering
F-35 Flight Test Highlights
Highlights of F-35 flight testing at NAS Patuxent River, Md., NAS Fort Worth Joint Reserve Base, and Edwards AFB, Calif.
F-35 Performs First Night Flight
The first night flight in the history of the Lockheed Martin F-35 program was completed on Jan. 19, 2012 in the skies above Edwards Air Force Base, Calif. Piloted by Lockheed Martin Test Pilot Mark Ward, AF-6, an F-35A conventional takeoff and landing (CTOL) variant, launched at 5:05 pm PST and landed after sunset at 6:22 pm
F-35 Airstart Testing
An F-35 test pilot talks about airstart testing at Edwards AFB, Calif., in early 2012.
F35 Air Show
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First Posted: 12/01/11 12:31 PM ET Updated: 12/01/11 04:04 PM ET