The first Ukrainian pilots have completed F-16 fighter jet training at a military base in Arizona, with others soon to follow this summer.

“The first batch has graduated, and other Ukrainian pilots are finishing their training here by the end of August,” Arizona National Guard spokesperson Capt. Erin Hannigan told VOA.

The graduates include a handful of Ukrainian pilots who had trained at Morris Air National Guard Base in Tucson, according to a U.S. official who spoke to VOA on condition of anonymity because of security sensitivities.

Out of an abundance of caution for the pilots’ safety, officials declined to provide an exact number of how many had graduated or the number of those who remain in F-16 training.

The 162nd Wing at Morris is considered the Air National Guard’s premier F-16 training unit and houses the Air Force’s only school dedicated to training pilots from more than 20 countries on the fighter.

Kyiv pleaded for Western aircraft when Russia launched its full-scale invasion of their country in February 2022. In August 2023, U.S. President Joe Biden approved a plan for Western allies to send F-16s to Ukraine once pilot training was complete.

Last August, Ukraine was gaining momentum in the conflict against Russia, but that was before a monthslong delay by Congress to approve new military assistance for Kyiv.

Since then, Ukrainian officials reported that troops were forced to ration supplies as ammunition ran low. Analysts say Russia has capitalized on Kyiv’s disadvantage to make gains on the battlefield.

Last month, Belgian Prime Minister Alexander De Croo said his country’s promised jets would be delivered to Kyiv by the end of the year.