South Africa's G20 presidency was meant to be an opportunity to get rich, powerful nations to pay attention to poorer countries' concerns such as burgeoning inequality, crippling sovereign debt and a lack of progress in the fight against climate change.

President Donald Trump’s attack on South Africa has brought relations between Washington and Pretoria to their lowest point since sanctions were imposed on the previous apartheid government in 1986. It is also likely to reduce or eliminate White House participation in this year’s G20 meeting,