South Korean, U.S. national security chiefs speak on North Korea

SEOUL (Reuters) - South Korea's national security chief, Kim Kwan-jin, spoke to U.S. National Security Adviser H.R. McMaster on Sunday following North Korea's latest missile test, South Korea's presidential office said. They agreed to strengthen cooperation to denuclearize North Korea, it said. (Reporting by Seoul bureau; Editing by Robert Birsel)