Canada said Tuesday it would accept proposals from four global defense contractors -- Airbus, Boeing, Lockheed Martin and Saab -- to replace 88 aging fighter jets.
The contract is reportedly valued at a minimum Can$15 billion (US$11.4 billion).
After 18 months of consultation with the industry, "the formal request for proposals has now been released to eligible suppliers," the government said in a statement.
On arriving in power in 2015, the government of Prime Minister Justin Trudeau cancelled an order for F-35 stealth fighters from Lockheed Martin meant to replace its antiquated fleet of CF-18 Hornets.
The defense contractors have until the spring of 2020 to submit initial proposals with a contract award due in early 2022 and delivery expected in 2025.
"This is the most significant investment in the Royal Canadian Air Force in 30 years," the statement said.
Canadian media reports indicate the contract is worth between Can$15 billion and Can$19 billion.
Sweden's Saab manufactures the multirole Gripen fighter aircraft, and Airbus is part of the consortium producing the Eurofigher Typhoon with BAE Systems.
Lockheed Martin manufacturers the F-35 stealth fighter and Boeing makes the F/A-18 Super Hornet.
France's Dassault Aviation took its Rafale out of the running in November because of technical requirements tied to Canada's membership in the "Five Eyes" signals intelligence sharing group of nations that the company could not meet, sources told AFP.
The Five Eyes group includes Canada, the United States, Britain, Australia and New Zealand.
The new aircraft's central role will be to patrol North American air space with the US Air Force under the joint US-Canadian North American Aerospace Defense Command (NORAD).
After a trade dispute with Boeing, the Trudeau government in 2017 announced that, instead of buying 18 new Super Hornets, it would buy 18 used F-18s from Australia as a stop-gap measure to add to its existing fleet.