Denmark's government said Monday that the training of Ukrainian pilots on F-16 jets has started and the retirement of Scandinavian country's fleet of aging U.S. fighters has been moved up two years.

The replacement fighters, F-35s, will be operative by 2025, acting Defense Minister Troels Lund Poulsen said. Initially, the switch was planned for 2027.

Lund Poulsen said that NATO-member Denmark “has taken the step of starting a training and further education effort for the Ukrainian pilots."

“We will also consider whether we should make a concrete donation to Ukraine of the Danish F-16 fighters, and how many there should be," he said.

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Ukrainian pilots must spend six to eight months of training before a possible donation of Danish F-16 aircraft can become a reality, Lund Poulsen told Danish broadcaster DR.

“This does not mean that you cannot make a decision beforehand. But (the F-16 planes) will be in Denmark until 2024,” Lund Poulsen said.

Denmark has ordered 27 F-35A fighter jets, which will replace the more than 40-year-old F-16s, of which Denmark has 30 operative planes. The switch to the F-35A Joint Strike Fighter jets is taking place from late 2023 to the end of 2025.

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Ukraine has long asked for Western fighter jets to help it resist the full-scale Russian invasion, which began in February 2022. Initially reluctant, the U.S. and other NATO countries recently agreed to allow Ukrainian pilots to receive training to on F-16 fighters, though none has yet committed to hand over any planes.

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