China's final warning
"China's final warning" () is a Russian proverb that originated as a Soviet political joke in the Soviet Union during the 1950s, referring to a warning that carries no real consequences. Origin and Cold War usage 
Relations between the People's Republic of China and the United States during the 1950s and 1960s were strained because of the Taiwan Strait issues. American military fighter jets regularly patrolled and performed fighter maneuvers the Taiwan Strait, which led to formal protests being regularly lodged by the Chinese Communist Party in the form of a "final warning". However, no real consequences were given for ignoring the "final warnings". The People's Republic of China released its first "final warning" to the United States for their reconnaissance flights on 7 September 1958, during the Second Taiwan Strait Crisis. At the time, the United States considered the Republic of China the sole legitimate representative of China and conducted reconnaissance flights in waters controlled by the People's Republic of China. China would then record such incidents, and issue a "final warning" through diplomatic channels for each incident that occurred. More than 900 Chinese "final warnings" had been issued by the end of 1964. Modern usage 
Following the dissolution of the Soviet Union, the proverb has retained its use as a common metaphorical catchphrase within the post-Soviet countries, especially in Estonia. The term was popularized in English-language social media during the lead-up to Nancy Pelosi's 2022 visit to Taiwan to refer to China's threats which are said to be superficially strong, but actually weak. See also

References 

Popular culture language
Proverbs
Russian proverbs
China–Russia relations
Foreign relations of China
Russian words and phrases