The Netherlands may not be able to deliver its first F-16 fighter jets to Ukraine until the end of 2024, the defence ministry has confirmed.

The Dutch air force owns 42 F-16s in total, 24 of which are used to defend Benelux air space and fulfil Nato duties.

The fleet is in the process of being upgraded to F-35s, but the F-16s will only be released once the replacements are running at full operational capacity.

That includes training pilots and technical staff, which may take until late 2024, a ministry spokesman said.

On Sunday prime minister Mark Rutte said the Netherlands would deliver the fighter jets to Ukraine, during a visit by the country’s president Volodymyr Zelenskyy, but did not say how many planes would be sent or give a timescale.

Twelve of the remaining 18 planes were due to be sold to US defence company Draken International, but the deal has been held up by a dispute over maintenance. The other six had been promised to Draken as compensation, NRC reported.

The defence ministry is looking at whether the two-seater jets can be used to train Ukrainian fighter pilots in Denmark or Romania, but they will not be available for active service.

“Delivery can only go ahead once all conditions have been met. We’re not talking about weeks here, but several months,” a ministry spokesman told NRC.

Denmark hopes to deliver up to six F-16s to Ukraine by the end of this year as its own fleet completes the transition to F-35s. Another eight are due to be sent next year and five more in 2025, making 19 in total.