South Africa has signed a new economic partnership framework with China aimed at securing duty-free access for South African exports, a move officials say will help cushion the impact of steep U.S. tariffs and expand trade with the country’s largest trading partner.

The agreement was signed Friday in China by South African Trade Minister Parks Tau and his Chinese counterpart Wang Wentao, according to a statement from South Africa’s Department of Trade, Industry and Competition.

The deal comes as Africa’s most industrialized economy seeks to diversify export markets following a sharp escalation in trade tensions with Washington. In August, U.S. …