After 15 years of rising trade and investment in Africa fuelled by China’s appetite for natural resources, Beijing is this week having to reassure its partners of its commitment.

Xi Jinping, China’s top leader, will have his work cut out at the Forum on China-Africa Cooperation, a triennial forum opening in Johannesburg today. A plunge in oil and commodities prices has cut the value of African exports amid fears of a rising Chinese trade surplus with the continent.

As Chinese growth slows, sub-Saharan Africa gross domestic product is expected to grow at 3.75 per cent this year, down from 5 per cent last year. China remains by far Africa’s single largest trading partner but the changing economic environment has made the relationship more complicated.