Just before leaving the G20 summit in Hamburg, Germany on Saturday, President Donald Trump held a bilateral meeting with Chinese President Xi Jinping. Following that high-level talk, the White House blasted out a transcript of Trump’s public remarks preceding the meeting, a document that called Xi “President Xi of the Republic of China.”

One problem: the “Republic of China” refers to Taiwan. China is referred to as the “People’s Republic of China.”

This is not the first time that Trump has blundered into the extremely sensitive question of Taiwan’s sovereignty.

Before he was even sworn into office, Trump angered China by taking a phone call from Taiwan’s president, something a U.S. leader has not done in decades. Though Trump defended the call at the time, he later told Xi he would honor the “one China” policy and not recognize Taiwan’s status as a sovereign nation.

On Saturday, according to the White House’s transcript, Trump told Xi: “It’s an honor to have you as a friend,” and called China a “great trading partner.”

Though the White House did not provide a translation of Xi’s remarks, Shanghai Media Group’s correspondent Ching-Yi Chang shared a translation with the U.S. press.

Xi, striking a more sober note than Trump, said “there is a lot of work needed to be done” on the “sensitive issues [that] remain in the China-U.S. relationship.”

“Differences emerge endlessly,” Xi reported said.