South Korea's top court cast doubt on Thursday on frontrunner Lee Jae-myung's eligibility to run for the presidency, while the resignations of the prime minister and finance minister shook the interim government in place since December's martial law.

Democratic Party nominee Lee Jae-myung will be retried on electoral violation charges, while the acting president has resigned and is expected to enter the race.

A new poll shows acting president Han Duck-soo, a 75-year-old technocrat, leading among conservative voters after Yoon Suk-yeol's impeachment South Korea's acting president, Han Duck-soo, is facing increasing pressure to run in the coming snap presidential election,