Singapore’s Air Force chief Maj. Gen. Kelvin Khong has given green light for F-35 fighter jet even though he acknowledged that logistics remain as a problem to be solved.

In a written reply to questions by the media, Maj. Khong said that the first four F-35Bs that Singapore is looking to buy would be located in the continental United States for initial training and testing.

Khong said that although most of the F-35’s developmental issues have been resolved in recent years, “some work still needs to be done on issues like logistics sustainment for the aircraft.”

Khong also stressed that Singapore chose to go after the F-35 following “careful consideration.”

Singapore submitted a letter of request for four F-35Bs with an option for eight more in April 2019. The U.S. State Department approved the possible sale in January this year.