The White House hit out on 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 US 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 US had indicated it was changing its mind over its boycott of the G20 leaders summit at the “11th hour” and wanted to take...