South Korean President Yoon Suk-yeol went viral for his hot mic reaction to President Biden's remarks at the United Nations General Assembly Wednesday.

Yoon, who took office in May, reacted to Biden's pledge to increase the U.S. contribution to the U.N. Global Fund, which would require congressional approval.

"How could Biden not lose damn face if these f---ers do not pass it in Congress?" Yoon asked his aides on a hot mic Wednesday, according to the South China Morning Post.

KIM JONG UN THREATENS TO USE NUCLEAR WEAPONS AGAINST US, SOUTH KOREA

Biden has repeated the talking point that America is respected again on the world stage since his election in 2020. 

Yoon's comments raised concern in his home country — strong U.S.-Korean relations are pivotal for mutual defense in the East Asian region.

AMERICAN MUSIC AWARDS CROWN SOUTH KOREAN BAND BTS ARTIST OF THE YEAR

"He wasn't speaking publicly on the stage but in passing, and although I don't know who recorded it and how, I actually think it should be verified," a South Korean official told reporters afterward, according to Yonhap.

"I think it's highly inappropriate to draw a link between private remarks and diplomatic accomplishments," the official added, referring to criticism that Yoon had created a diplomatic disaster. "It's quite regrettable that a diplomatic disaster is being talked about over something like that when he is doing everything to complete a demanding schedule in the national interest of the Republic of Korea."

United States, South Korean and Japanese military forces cooperated last month in a trilateral missile defense exercise — the first of its kind in years.

The drills began Aug. 8 and ran through Sunday, boasting the first formal cooperation of its kind since December 2017.

The exercise served to reassure the allied nations of their individual and joint commitments to mutual defense. Notably, the cooperation between South Korea and Japan could serve to ease cultural tensions that have lingered in recent years.