South Korea's main opposition party introduced a bill to impeach acting President Han Duck-soo on Thursday, a day before it plans to seek a vote on the move, which could deepen a constitutional crisis triggered by a short-lived martial law.

South Korea’s parliament voted to impeach President Yoon Suk Yeol on Saturday in an extraordinary rebuke that came about after his own ruling party turned on him following his refusal to resign over his short-lived martial law attempt.

For the United States, the turmoil in South Korea is potentially disruptive to its geopolitical agenda in East Asia.