The White House hit out Thursday at South Africa's leader for “running his mouth” over the United States' boycott of this weekend's Group of 20 summit in Johannesburg in another diplomatic rift between the U.S. and a country that has been especially targeted for criticism by President Donald Trump.

South African leader Cyril Ramaphosa told reporters in Johannesburg that the U.S. had indicated it was changing its mind over its boycott of the G20 leaders summit at the “late hour" and wanted to take part.

White House press secretary Karoline Leavitt said that was not true and had sharp words for Ramaphosa in response.

“I saw the South African president running his mouth a little bit against the United States and the president of the United States earlier today, and that language is not appreciated by the president or his team,” Leavitt said at the White House.

She said the U.S. was sending a diplomatic official to the summit to simply recognize that the U.S. will take over the rotating presidency of the bloc and host near year’s G20 summit.

A representative from the U.S. Embassy in South Africa will attend the formal handover ceremony at the end of the two-day summit that opens on Saturday, but Washington still won’t take part in any talks, a White House official said. The official wasn’t authorized to speak publicly and spoke on condition of anonymity.