President Cyril Ramaphosa is joining other world leaders at the G7 Summit in Cornwall, southwestern England this week.
At the meeting of most of the world's most powerful countries, he is expected to push for a temporary patent waiver on Covid-19 vaccines.
South Africa and India have been driving a campaign to achieve this.
In a surprise move, the US last month expressed support for the waiver, a sharp reversal of its previous position. France and Russia also support the move, while Germany and the UK oppose the waiver.