Acting President Lee Ju-ho on Friday called for maintaining a watertight readiness posture against North Korea's possible provocations, as he assumed the interim leadership following the resignations of the prime minister and finance minister.

Prime Minister Han Duck-soo has been mulling whether to contest the election, while the main opposition candidate and front-runner suffered a setback in court.

South Korea’s main liberal opposition party has tapped its former leader Lee Jae-myung as presidential candidate in the June 3 vote