Ukraine has received the first F-16 fighter jets that it has sought for months to fight back against an onslaught of Russian missile strikes, a U.S. official confirmed to the Associated Press.

Ukraine has been pushing its Western allies for F-16s for Ukraine for months, saying they were critically needed to fight back against the onslaught of missiles Russia has fired against it. The F-16 is specialized in suppressing enemy air defenses.

The U.S. has also been training Ukrainian pilots on how to fly the jets and has already graduated the first group of pilots on its operation.

It's not clear how many jets were provided in the first tranche or which nations provided them. The Ukrainian government has not confirmed receipt of the jets.

The arrival of the jets was first reported by Bloomberg.