"There is no war in Ba Sing Se" is a saying that originates from Nickelodeon's animated series, Avatar: The Last Airbender, and is utilized as a sarcastic expression implying a statement is extremely false, often with propagandistic implications.
"There is no war in Ba Sing Se" origins
The second season of Avatar: The Last Airbender featured an episode entitled "City of Walls and Secrets,” which aired on September 22, 2006.
During that episode, the character Jet takes part in a tea show brawl...