U.S. Secretary of State Antony Blinken met South Korea's acting leader Choi Sang-mok in Seoul on Monday. Millions should prepare for disrupted travel and winter conditions as a fierce storm is set to bring ice, snow and freezing rain to much of the U.S.

South Korea's acting President Choi Sang-mok said on Thursday immediate action must be taken if a special inspection of all Boeing 737-800 aircraft operated in the country finds any issues as authorities ramp up a probe into Sunday's deadly air crash.