Seoul, South Korea — South Korea’s acting leader, Prime Minister Han Duck-soo, said Thursday he is resigning to take on “heavier responsibility” amid expectation he will run in next month’s presidential election.

South Korea's former President Yoon Suk Yeol is to be additionally charged with abuse of authority. The ex-president is already being tried for insurrection, over his failed bid to impose martial law.

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.