Within hours of the newscast, Mr. Trump had fired off a tweet claiming that there was “large-scale killing” of white farmers in South Africa, and that he had directed the State Department to “closely study the South Africa land and farm seizures and expropriations.”

The White House has directed federal agencies to stop work with the upcoming Group of 20 (G20) conference slated to be held later this year in South Africa amid outcry from President Trump over the treatment of white South African farmers.