Despite British recognition of the new regime, Communist seizure of U.S. consular property in Beijing prompted the United States to recall all consular officials from China in January 1950.
Some background
In August 1949 the U.S. Department of State issued the China White Paper, which stated that the United States had stayed out of the Chinese civil war because it neither should nor could have influenced the outcome.
In October 1949, after the Nationalists were driven from mainland China, Mao Zedong proclaimed the establishment of the People’s Republic of China.
Shortly before the proclamation of the new Chinese government, U.S. Ambassador John Leighton Stuart met with Communist leaders to discuss U.S. recognition of the the new regime. Further negotiations faltered when Mao announced his intention to lean towards the side of the Soviet Union.
Source: https://history.state.gov/countries/issues/china-us-relations
