The office of South Korean President Moon Jae-in has responded sharply to comments by a conservative lawmaker who accused him of acting as the "top spokesman" of North Korean leader Kim Jong Un.

The Blue House said in a statement on Tuesday that Na Kyung-won's comments were an insult to both Moon and South Koreans wanting peace and demanded an apology.

Na's speech at the National Assembly was interrupted for about 20 minutes after legislators from the ruling liberal party reacted angrily to her comments, approaching the podium and engaging in shouting matches with opposition lawmakers.

Moon has held three summits with Kim and lobbied hard to revive nuclear talks between Washington and Pyongyang, which resulted in two meetings between Trump and President Donald Trump.