South Africa has tried for months to negotiate a deal with Washington and offered to buy U.S. liquefied natural gas and invest in American industries in exchange for a lower tariff.

South Africa, which has a strained relationship with President Trump, is the only African country singled out in the announcement with a 30% tariff increase on August 7.

South African products exported to the US will be hit by a 30% tariff from 7 August, President Donald Trump has announced. South Africa faces the highest rate in sub-Saharan Africa, reflecting Trump's strained relationship with the government of President Cyril Ramaphosa.

South African scientists have launched an anti-poaching campaign in which rhino's horns will be injected with a radioactive material. The group, from the University of the Witwatersrand, said the process is harmless to rhinos but will allow customs officers to detect smuggled horns as they're transported across the world.

A new initiative in South Africa is safely placing radioactive isotopes into rhino horns and using existing nuclear security infrastructure to detect and deter illegal trade. Sean Hogan has more.