MELBOURNE, Australia — Taiwan's state-owned Aerospace Industrial Development Corporation (AIDC) has confirmed earlier local media reports that it started upgrading Lockheed Martin F-16 Fighting Falcon jets for the country's Air Force.

In a statement, AIDC said four Taiwanese Air Force F-16s have entered its new facility in Taichung and the upgrading work on the fleet of 144 F-16s is expected to be completed within six years. AIDC Chairman Anson Liao had previously said that at full capacity, the new facility will be capable of upgrading 24 aircraft per year.

Taiwanese media had earlier reported that 10 F-16s were due to undergo upgrades at AIDC, but delays in software testing in the US means that only four aircraft will complete the upgrade program in Taiwan this year.

According to the original 2011 Defense Security Cooperation Agency Foreign Military Sale (FMS) notification, the Taiwanese F-16 upgrade request included Northrop Grumman AN/APG-83 Active Electronically Scanned Array (AESA) radars, new mission computers, Embedded Inertial Navigation Systems/Global Positioning Systems and the Terma ALQ-213(V) Electronic Warfare Management Units.

Taiwan had also sought to upgrade its existing Raytheon AN/ALQ-184 electronic countermeasures (ECM) pods to incorporate Digital Radio Frequency Memory technology or purchase new ECM pods for its F-16s. It had also sought new targeting pods, dual-mode GPS/laser-guided bombs and the Raytheon AIM-9X agile air-to-air missile for its F-16s.

The FMS request had estimated the value of the entire program to be $5.3 billion, with Taiwan having already set aside almost $3.5 billion in its budget to cover part of the program. The lead contractor for the program will be Lockheed Martin, which has already flown a Taiwanese F-16A fitted with the AN/APG-83 AESA radar in the United States back in 2015.

Taiwan's F-16s are relatively new and capable aircraft despite carrying the F-16A/B designation, with deliveries starting in the mid-1990s and being completed only in 2001. In addition to Taiwan, two other F-16 users in the Asia-Pacific region

— South Korea and Singapore — have also contracted Lockheed Martin to carry out upgrades to their respective fleets.

Speaking to media during the Singapore Airshow in February 2016, Randy Howard, the director of business development for Lockheed's Integrated Fighter Group, revealed that the three nations will have most of their respective fleets upgraded in-country with upgrade kits shipped over by the company.

He added that initial aircraft may be upgraded by Lockheed Martin in the United States, but subsequent aircraft will be upgraded by local industry, with Lockheed assisting and consulting.

US arms sales to Taiwan are usually fraught affairs, as neighboring China sees Taiwan as a renegade province and is firmly opposed to improving the capabilities of the Taiwanese military and has successfully lobbied hard to restrict any significant arms sales to Taiwan, including preventing the Bush and Obama administrations from selling newer F-16C/Ds to Taiwan.

The US recognizes as legitimate China's government, and also officially considers Taiwan as a part of China; however, the United States maintains de facto diplomatic relations with Taiwan's government, and the Taiwan Relations Act enacted by Congress in 1979 states that "the United States will make available to Taiwan such defense articles and defense services in such quantity as may be necessary to enable Taiwan to maintain a sufficient self-defense capability."