OTTAWA – The federal government has announced the official request for proposals for Canada's 88 new fighter jets to replace the aging CF-18 fleet and upgrade the Air Force's capabilities.

The requests for proposals have been sent to the four suppliers in the running for the $19-billion competition: Sweden's Saab Aeronautics, U.K.'s Airbus, and American companies Boeing and Lockheed Martin.

Bidders will have two opportunities to show they can meet the security and interoperability requirements, and will be receiving feedback from the government about any compliance issues. The security aspect of the pitches is due in fall 2019, with final proposals submitted by March 2020.

"The government will deliver the aircraft that meet Canada’s needs, while ensuring good value for Canadians," reads the news release from Public Services and Procurement Canada.

In an interview on CTV News Channel, Public Services and Procurement Minister Carla Qualtrough said that while “it’s taken far too long,” she is sure the government has got it right.

“I can assure every man and woman in the Canadian Air Force that we are working tirelessly to get them the equipment they need,” she said.

The estimated budget for this "once in a generation" procurement does not include the cost for sustainment, after bringing these aircraft into service.

According to the news release, the proposals will be assessed on technical merit, which will have a weighting of 60 per cent, cost with a weighting of 20 per cent, and economic benefits weighted at 20 per cent.

Bidders will have to provide a plan for economic benefits to Canada that are equal to the value of their proposed contract. The weighting of this aspect of the proposal has been increased by five points, with the maximum points going to the suppliers who offer contractual guarantees for this reinvestment in Canada.

In statements to CTV News, both Boeing and Airbus say they are currently reviewing the government’s request for proposal and welcome the opportunity to demonstrate why their jets are best suited to meet Canada’s aerospace needs.

Replacing the military's existing jets—purchased in the ‘80s—has been a work in progress for nearly a decade, with the previous Conservative government announcing in 2010 that it had selected the Lockheed Martin F-35s for a multi-billion dollar sole-source deal. Under that plan new jets were set to be delivered by 2016 but the deal erupted in political controversy over accusations the Tories misled Parliament about the true cost of the planes.

Then, during the 2015 federal election campaign, Justin Trudeau vowed that if the Liberals formed government they would not purchase the F-35s and would instead look for a cheaper option. Though just months later Defence Minister Harjit Sajjan signalled that the F-35 would not be excluded from the "open" fighter replacement competition.

The Liberals launched the procurement process to replace the fleet in 2017, with the planned timeline of having a contract awarded in early 2022, with the first aircrafts delivered in 2025. That timeline has been maintained in today’s request for tenders.

The Liberals first said they'd be purchasing 18 Boeing Super Hornets in the interim, before backing out of that agreement amid tensions between the U.S. aerospace giant and Canadian company Bombardier. In November 2018 the government settled on procuring 18 used F-18s and up to seven additional non-flyable aircrafts for parts and training, from Australia.

The initial draft tender for these 88 new jets was issued in October 2018 and suppliers provided the federal Liberals with their recommendations for the formal invitation to these major aerospace manufacturers to submit their proposals. Officials say that they received requests to, and made thousands of changes from the draft versions of the proposals issued today.

Meanwhile, Canada continues to pay what has amounted to more than $500 million to remain a partner in the F-35 development program over the last 20 years.

The opposition Conservatives were quick to criticize the amount of time it has taken to get to this point.

"It is inexcusable that Justin Trudeau spent the past four years dithering on the fighter jet file. Instead of rolling up his sleeves and procuring a new jet for our Royal Canadian Air Force, he decided to delay the selection of a new jet… Countries around the world have selected new fighter jets in under two years," said Conservative defence critic James Bezan.

Bezan, noting that the winning bid won’t be selected until after the next federal election, said that a Conservative government would "immediately select a new fighter jet through a fair and transparent competition."

Qualtrough said that the decision about which supplier is selected will be absent of any political considerations. She said the Conservatives were the ones who “botched” the major military procurement in the first place, alleging the Liberals “inherited such a mess.”

With files from CTV News' Michel Boyer and The Canadian Press