The White House made a faux pas on Saturday by apparently confusing China with Taiwan, a sensitive topic in Beijing.
U.S. President Donald Trump and Chinese President Xi Jinping held talks on the sidelines of the G20 summit in Hamburg, with the White House issuing a transcript of Trump's comments after they appeared together.
But the document sent to reporters referred to Xi as president of the "Republic of China," which refers to Taiwan, while China is officially known as the "People's Republic of China."
Beijing regards Taiwan - which has had a separate government since Chinese Nationalists fled there in 1949 after losing a civil war to the Communists - as a renegade province.
Its "One China" policy requires other countries to avoid formal diplomatic recognition of Taiwan, most recently leading Panama, one of Taiwan's few remaining allies, to cut ties with Taipei last month.
Trump first ruffled feathers in Beijing after his November election victory, when the president-elect accepted a congratulatory phone call from Taiwan President Tsai Ing-wen, despite the US having broken off relations with the island in 1979.
Recently, Trump has been openly critical of Beijing's efforts to reign in North Korea's nuclear program, and the two powers have clashed over the South China Sea, which is claimed by China as well as several other countries.
While Xi said after his Saturday meeting with Trump that Beijing would "like to work with the U.S.," he last week described the relationship as afflicted by "negative factors."
According to some reports, it was the White House's second gaffe of the day, after earlier it mistitled Japan's prime minister as "President Abe of Japan."