Lee Ju Ho steps in as interim president of South Korea

Lee Ju Ho, South Korea's deputy prime minister for social affairs and education minister, on Friday took over as the country's interim president, replacing Han Duck Soo in the role.

Han was meant to be replaced as president by South Korea's Deputy Prime Minister Choi Sang Mok, but he stepped down late on Thursday after the opposition Democratic Party moved to impeach him.

Lee on Friday instructed the military to raise its readiness posture to the "highest level," the official news agency Yonhap reported.

"The government should do its utmost so as to continue state governance stably without any vacuum in state affairs or any confusion," Yonhap quoted Lee as saying in the directive.

Han was prime minister from 2022 until Thursday. He also assumed the presidency in an acting capacity after Yoon Suk Yeol was suspended as president following his sudden declaration of martial law on December 3, citing vague threats from political opponents.

The martial law declaration, which was only in effect for a few hours before it was rescinded, threw South Korean politics into disarray.

The Constitutional Court has ruled in early April that Yoon abused his power and permanently removed him from office. That decision set the clock running on the presidential election, which has been set for June 3.

Han's resignation has fuelled speculation that he may run in the country's upcoming election. He confirmed his bid on Friday.