South Korea's President Yoon Suk-yeol has been facing criticism in his country for allegedly using foul language captured on video in New York.

Yoon was caught on camera making a private remark to his aides at a meeting hosted by US President Joe Biden on Wednesday. Yoon had made his first address to the UN General Assembly the previous day.

South Korean media say the video shows Yoon referring to US lawmakers with a vulgar term. The video went viral on the Internet.

Opposition party members in South Korea criticized Yoon for undermining national dignity and defaming the United States, a key ally.

The South Korean government said the remark did not refer to US lawmakers. It said Yoon was expressing concerns about his own country's opposition parties.