Norway said on Friday that the United States had withdrawn its fighter jets from large-scale NATO exercises scheduled for March in northern Norway.

Lieutenant Colonel Espen Solimdal of the Norwegian Armed Forces told local media that U.S. F-35 fighter jets would not take part in the drills focused on Arctic security.

He said the decision meant that between 100 and 150 U.S. troops would not travel to Norway, adding that they would be deployed “to other places in the world.”

Solimdal noted that the absence of U.S. aircraft would affect the air component of the exercise, saying the United States was “engaged in its own race,” without elaborating further.

There was no immediate comment from the U.S. Defense Department.