The Netherlands and Denmark will supply F-16 fighter jets to Ukraine, with first deliveries due around New Year, the prime ministers of the two NATO countries announced Sunday during visits by Ukrainian President Volodomyr Zelenskyy.

The pledge is the first real promise of F-16's for Ukraine's armed forces and comes a few days after the United States approved the possible delivery of the fighter jets by the two countries.

Zelenskyy called the decision a "breakthrough agreement" and said the planes would help strengthen Ukraine's air defenses and help its counteroffensive against Russia's 2022 invasion.