OTTAWA -- Federal officials sought to demonstrate Thursday how much work has been done to replace Canada's aging CF-18 jets, but say the details of the evaluation will be kept secret while cabinet weighs whether to continue with the oft-maligned F-35 program.

Members of an independent panel that looked at what fighter aircraft are available as replacements for the 30-year-old Hornets made a public appearance to emphasize the depth and impartiality of their assessment, 14 months in the making.

That analysis, which essentially fact-checks the air force's market evaluation, has been turned over to the government. It lays out what each of the four contenders can do.

Separately, a committee of deputy ministers overseeing the replacement program has handed a recommendation to the Harper cabinet.

The government could continue with the F-35 program, which has been on hold. It could choose an open competition involving the stealth fighter and other aircraft, including the Boeing Super Hornet, Eurofighter's Typhoon, Dassault's Rafale, and possibly the Saab Gripen.

Rewriting the air force's statement of requirements, which critics say was rigged in favour of the F-35, is another possibility and one that could postpone a replacement decision.

No timeline was given, but government insiders said Thursday a substantive decision was expected soon.

Prime Minister Stephen Harper told the House of Commons that the government found the report "helpful" and restated earlier pledges to make a decision in the best long-term interest of the military.

In April 2012, auditor general Michael Ferguson slammed the Harper government's plan to buy 65 stealth jets, accusing Public Works and National Defence of low-balling the cost and not doing their homework.

The panel itself does not make a recommendation among the four fighter aircraft it examined, including the F-35, but instead left the choice up to the committee of deputy ministers and ultimately the cabinet.

"This is a democracy, not a technocracy," said Phil Legasse, a panel member and University of Ottawa defence expert.

"Ministers are responsible for making decisions. They are given the information on which to make those decisions. It is not for technical experts to decide government policy."

Another panel member, Keith Coulter, said they had a mandate to be independent and to challenge the air force's information and assumptions.

"We saw it as our job to challenge," said Coulter, a former fighter pilot. "We constantly asked hard questions, often insisted on in-depth analysis where we thought this was needed or might help, and always provided frank input, feedback and advice."

Despite the assurances, the Liberal defence critic described the evaluation as paper exercise to support proceeding with the F-35.

"This entire process has just been an elaborate ruse to justify a decision they planned from the beginning," said Joyce Murray.

But Coulter denied that, saying the exercise "wasn't set-up."

The evaluation was measured against the government's current defence policy, which outlines six primary missions for the air force. But that policy is now undergoing a full rewrite because elements were considered unaffordable in the current economic climate.

Murray said cabinet cannot make a decision on the CF-18s in isolation without weighing what happens to the rest of the defence budget, which has been cut by as much as $2.1-billion annually since 2011.

"I think Canadians will want to know what equipment can the Armed Forces not replace, if this massive purchase were to go ahead," she said.