South Korea, Japan and the United States will begin their annual Freedom Edge military drills on September 15, aiming to sharpen cooperation in the air, at sea and in cyberspace, Reuters reported.

Officials in Seoul said the exercises come at a time when North Korea’s nuclear and missile threats are growing, making close coordination between the allies more important than ever.

The drills, held every year, are designed to strengthen joint readiness and reassure the region of the allies’ commitment to peace and stability. Military leaders stressed that all activities will be carried out in line with international law, according to Reuters.