North Korean leader Kim Jong Un supervised drills by the nation’s air force and underscored the need for a step-up in war preparation, state media said on Saturday.

Kim, who inspected anti-aircraft combat and air strike drills by North Korea’s 1st Air Division on Thursday, called for “all units in the entire military” to bring about “a breakthrough in war preparation”, KCNA reported.

Footage of the drills on North Korean state TV showed a MiG-29 jet launching a missile, which appeared to be a North Korean version of a Russia-developed mid- to long-range air-to-air missile, said Hong Min, North Korea analyst at the Korea Institute for National Unification.

So far this month, Kim has overseen a missile test, inspected tank and munitions plants, made a rare visit to the Russian embassy in Pyongyang reaffirming the country’s alliance with Russia, and supervised tank firing drills and special operations unit training.

North Korea also slammed the US State Department for placing it on a list of countries that do not fully cooperate with US counterterrorism efforts. Pyongyang has been placed on the list every year since 1997, South Korea’s Yonhap News Agency said.

“The more the US provokes the DPRK with unnecessary and inefficient malicious acts, the further it will escalate the irreconcilable hostility between the DPRK and the US,” a North Korean Foreign Ministry spokesperson said, using the country’s official name, the Democratic People’s Republic of Korea.

“The DPRK will... take effective and proper measures to cope with the US hostile provocations in all spheres.”