COPENHAGEN, Denmark (AP) — Four F-35 fighter jets landed Thursday at an airbase in Denmark in the first installment of the U.S.-made planes ordered by the NATO member to replace its aging fleet of F-16s, some of which have been promised to Ukraine.

Dignitaries and officers clapped as the planes, in Danish Air Force colors, did several flyovers before landing at the Skyrdstrup Air Base.

Ukraine has been asking for Western fighter jets to help it resist the Russian invasion that began in February 2022. The United States recently gave its approval for Denmark and the Netherlands to provide Ukraine with the American-made jets.

Last month, the two countries said they would donate F-16 aircraft to Ukraine, with Denmark pledging 19 and the Netherlands an unspecified number. Denmark said it would need to receive new F-35s first, and Danish Prime Minister Mette Frederiksen said in August that she hoped the first six F-16s could be handed over to Ukraine around New Year.

NATO member Norway also has indicated its intention to donate F-16s to Ukraine.

Denmark said in June that the training of Ukrainian pilots on F-16 jets had started at the Skrydstrup Air Base, which is about 210 kilometers (130 miles) west of Copenhagen on the Jutland peninsula.

Denmark has ordered a total of 27 F-35 fighter jets for $2.2 billion. They will replace the country’s fleet of 30 F-16s, which are more than 40 years old, in a transition that will last through the end of 2025.

Following Thursday’s ceremonial arrival, the initial four planes will be formally handed over to Denmark by the U.S. manufacturer Lockheed Martin on Oct. 1.

F-16s have been deployed in countries and regions including the Balkans, Afghanistan, Syria and Iraq, where their operations have included patrolling airspace, dropping bombs and supporting soldiers on the ground. Iceland and Baltic countries also have used them to assert their sovereignty in “air policing.”