The UK has signed an economic partnership agreement with the Southern African Customs Union, and Mozambique, which the British government says will allow business to keep trading freely after the UK leaves the European Union, which is currently due to happen on 31 October.
It allows businesses to continue to trade on preferential terms with South Africa, Botswana, Lesotho, Namibia, Eswatini and Mozambique.
South Africa’s Trade Minister Ebrahim Patel said the deal would give the southern African states a soft landing in case of a no-deal Brexit.
UK Trade Minister Liz Truss said: "This is a major milestone as the UK prepares to become an independent trading nation once again, and we are helping businesses get ready to trade with the most exciting markets around the world."
The UK is one of South Africa's largest trading partners, with bilateral trade valued at about $9.5 billion in 2018.