DARWIN, Australia — Singapore is considering buying another F-35 variant despite already selecting and receiving U.S. approval for the “B” version, which can take off from short runways and land vertically, according to a top official with the procurement effort.

Speaking to media during a multinational air combat exercise in northern Australia, Major Zhang Jian Wei, who leads his country’s office in charge of the next-generation fighter project, left open the possibility that the island nation may choose another variant. The other two F-35 versions are the “A” — which operates from conventional runways — and the “C” — which is used on aircraft carriers.

He did not give a timeline for how long the evaluation will take, only saying Singapore will “make further decisions when ready.”

Singapore selected the F-35B as its candidate to replace its fleet of 60 F-16C/D multirole fighters, which are receiving upgrades but are due for retirement beginning in the early 2030s. It is expected Singapore will order more fighters in tranches to replace the fleet, per its normal practice.

Zhang, who leads a team of four subject matter experts at his project office, said the ongoing exercise Pitch Black in Australia has served as a “valuable opportunity” for the Republic of Singapore Air Force to understand the ability of the F-35 to operate with other assets and act as a force multiplier in a large force employment setting.

The F-35 is taking part in the exercise for the first time, with host Australia flying F-35As while U.S. Marines use their F-35Bs.

The Singaporeans engaged with both detachments at the exercise, with Lt. Col. Richard Behrmann, operations officer at Marine Aircraft Group 12 based in Iwakuni, Japan, telling Defense News that the Marines began an “excellent dialogue” with the Republic of Singapore Air Force in the months before the exercise. Planning involved the F-35 Joint Program Office, and Singapore sent teams to the Marine Corps’ F-35B detachment at RAAF Base Tindal “to observe operations, interact with maintenance personnel, look at our planning spaces and generally discuss the way that we operate.”

Zhang noted that Singapore signed a letter of offer and acceptance in 2020 for the F-35 and has since gained increased access to program information exclusive to operators of the stealthy fifth-generation fighter. The country has also been able to interact with global F-35 operators as part its evaluation process by attending a user conference in May involving operators from Europe and the Pacific region.

Personnel from Zhang’s office also visited F-35 facilities and attended a training session in Forth Worth, Texas, with American instructors. Attendees also used high-fidelity simulators, which Zhang said enabled better understanding of the operational capability of the aircraft as well as engineering and maintenance requirements.

Singapore received U.S. State Department approval in January 2020 to acquire an initial tranche of four F-35Bs with an option for eight more aircraft in a deal valued at $2.75 billion, with deliveries expected to start from 2026.

The small Southeast Asian island nation is due to move its F-16 training detachment at Luke Air Force Base in Phoenix, Arizona, to Ebbing Air National Guard Base at Fort Smith, Arkansas, in 2023. It will eventually transition to F-35B training following the delivery of its first aircraft.

Mike Yeo is the Asia correspondent for Defense News.

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