Three companies have submitted bids for a contract worth $6.9 billion to supply 60 fighter aircraft to South Korea, the country's arms procurement agency said Monday.
Boeing's F-15 Silent Eagle, Lockheed Martin's F-35 Lightning II and the Eurofighter Typhoon will vie for the order, the Defense Acquisition Program Administration (DAPA) said in a statement on its website.
Monday was the bidding deadline, with the winner to be selected in October. The contract is worth eight trillion won ($6.9 billion).
DAPA also plans to spend some 1.8 trillion won on 36 attack helicopters, with Boeing's Apache, Eurocopter's Tiger and Turkey's T129 thought to be in competition.
Tensions with North Korea have been high in recent years. The North and South remain technically at war because a peace treaty was never signed formally to end their 1950-53 conflict.
The massive weapons acquisition being pushed through in the last year of President Lee Myung-Bak's presidency has sparked opposition criticism.
The Democratic United Party urged the government not to rush through the programme.
"Further study and review are needed before the government goes ahead with the purchase of weapons. If necessary, this project should be handed over to the next government," it said in a statement last month.
South Korea has already bought 60 of Boeing's F-15 fighter jets since 2002 under the first two stages of a fighter modernisation programme.