SEOUL, South Korea (AP) — North Korean leader Kim Jong Un has toured the country’s key weapons factories producing artillery systems, engines for cruise missiles and drones, and launch vehicles for nuclear-capable ballistic missiles, and pledged to speed up efforts to advance his military’s arms and war readiness. State media reported Sunday that Kim’s three-day inspections came as the U.S. and South Korea prepared for their next round of combined military exercises planned for later this month to cope with the growing North Korean threat. Some experts say Kim’s tour of the weapons factories could be related to possible military cooperation with Moscow as Russian President Vladimir Putin reaches out to other countries for support in the war in Ukraine.