South Korea plans to kick-start a long-delayed program to build fighter jets despite lingering skepticism over its feasibility and technological barriers, officials said Sunday.

The ambitious project, called KFX or Boramae, is aimed at producing F-16-class fighter jets. The military aims to introduce the first model by 2023 and deploy 120 units over the following several years, officials said.

“The Boramae project will kick into high gear this year to develop 120 Korean-made fighter planes,” a senior military official said on condition of anonymity due to the sensitivity of the matter.

The Defense Ministry secured 20 billion won ($19.1 million) for the program this year.

The initiative was incepted in 2000 to replace the military’s aging F-4 and F-5 warplanes with homegrown ones starting 2020, but has dragged on due largely to controversy over its feasibility.

The Joint Chiefs of Staff Council has decided to shorten the period of the project from the original 20 odd years, as the Air Force faces a shortage of about 100 fighters in 2019, when nearly all the F-4s and F-5s are expected to be decommissioned.

The Air Force says it needs at least 430 fighter jets to prepare for possible wartime operations ― some 100 high-end, 200 middle-range and 100 low-end models.

In late November, the military decided to buy 40 F-35 stealth jets from Lockheed Martin for deployment from 2018-21.

With Seoul seeking more sophisticated technologies, observers raised the possibility of a purchase of 20 additional warplanes from Boeing or the European Aeronautic Defense and Space Company, which displayed more willingness to share their expertise than Lockheed.

By Shin Hyon-hee (heeshin@hearldcorp.com)