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.

Choi, 61, a veteran economic technocrat who has served for more than 30 years at the finance ministry, takes on an unprecedented role as successor to an impeached acting leader.

Finance Minister Choi Sang-mok became on Friday South Korea's second acting president in two weeks, as lawmakers voted to impeach the current acting leader, Prime Minister Han Duck-soo, fuelling political uncertainty in Asia's fourth-largest economy.