MELBOURNE, Australia — Indonesia is looking to acquire two squadrons of new F-16 fighter jets from the United States, even as it pushes ahead with plans to buy Russian Sukhoi Su-35s, according to the chief of the Indonesian Air Force.

In remarks carried by state-owned national news agency Antara on Oct. 28, Air Marshal Yuyu Sutisna said the southeast Asian nation plans to submit a request to buy two squadrons of Lockheed Martin F-16 Block 72 fighters by January 2020.

Sutisna said the F-16 acquisition will be part of Indonesia’s next five-year strategic plan, running from 2020-2024, Antara reported. The officer made the announcement during a visit to Roesmin Nurjadin Airbase in Pekanbaru, the capital of Riau Province on the western Indonesian island of Sumatra.

He did not elaborate on the exact number of F-16s Indonesia plans to buy, as that will depend on how much money the government can set aside for the acquisition, which will be collected separately from the already allocated defense budget of $7.7 billion.

Sustina also said Indonesia is still pursuing the Russian Sukhoi Su-35 Flanker interceptor, although that effort has encountered several delays. The Su-35s are earmarked as a replacement for Indonesia’s Northrop F-5E/F interceptors, which are no longer in service.

The already-protracted contract negotiations with Russia are further complicated by Indonesia’s concerns over CAATSA, an American law that could apply a variety of sanctions to individuals and organizations that engage in “transactions with the intelligence or defense sectors of the Russian Federation.”

Indonesia is seeking 11 Su-35s from Russia and hopes to pay for these with both cash and the exchange of a variety of local commodities.

Indonesia’s Air Force operates Su-27SKs and Su-30MK2s acquired earlier this decade from Russia. Indonesia has a policy of diversifying its arms purchases to reduce over-reliance on a single source of supply.

The island nation also operates earlier versions of the F-16, with 18 single-seat F-16Cs and five two-seater F-16Ds delivered under the Peace Bima Sena II program. The jets are used by the Air Force’s 3 and 16 squadrons alongside Block 15 F-16A/B aircraft, of which eight were acquired in the 1980s.

The F-16C/Ds are former U.S. Air Force and Air National Guard aircraft that were in storage and subsequently offered to Indonesia in 2011 under the U.S. Excess Defense Articles program. Indonesian Air Force engineers are locally upgrading the F-16A/Bs with assistance from Lockheed Martin.

The 24 jets were upgraded with the installation of a new modular mission computer, Link 16 data links and a self-protection suite under a Foreign Military Sales package worth $750 million before delivery to Indonesia, although one was subsequently destroyed in a fire in 2015 after running off the runway during its takeoff roll.