The Japanese government plans to closely monitor developments in South Korea while maintaining working-level communication with Seoul so that the bilateral relations is not adversely affected.

Six opposition parties in South Korea on Wednesday submitted a bill to the National Assembly to impeach President Yoon Suk-yeol. The move came after Yoon declared emergency martial law on Tuesday night and lifted it hours later.

Prime Minister Ishiba Shigeru said on Wednesday that good relations between Japan and South Korea are crucial for peace and stability in the region, and that he is following developments in South Korea with grave concern.

Ishiba discussed the situation with Cabinet members including Foreign Minister Iwaya Takeshi and Defense Minister Nakatani Gen on Wednesday night.

Some government officials hold the view that the developments in Seoul have made it difficult for Japan and South Korea to engage in their leaders' shuttle diplomacy for the time being.

Nakatani, who was making arrangements to visit South Korea by the end of the year, will likely shelve the plan, citing difficulties amid the current situation.

As ties between Tokyo and Seoul improved significantly under Yoon and Ishiba's predecessor, Kishida Fumio, some Japanese government officials are concerned that the bilateral relations could deteriorate, depending on how the situation in South Korea unfolds.