The United States has apologized to China for misusing President Xi Jinping's title in a transcript, Foreign Ministry spokesman Geng Shuang said on Monday.

According to Geng, China protested to the US over the misuse and the US acknowledged it was a technical mistake and had made a correction.

"The US has made an apology to China," he told reporters at a daily news conference in Beijing.

The White House issued a transcript on Saturday about the meeting between Xi and US President Donald Trump during the G20 summit. However, the header described Xi as president of the Republic of China instead of president of the People's Republic of China.

The mistake was on the transcript's header only, and was not in the full text or in Trump's remarks to Xi in Hamburg, Germany.

The White House has altered the transcript to read simply "President Xi of China".

Wang Dong, associate professor at the School of International Studies at Peking University, told the Associated Press he believes the error was not intentional, but still revealed a lack of knowledge in Trump's foreign policy team.

"It shows a deficiency in professionalism on the part of the White House staff in terms of diplomacy," Wang said.