ANC veteran Dumisani Kumalo has died "peacefully" at his home, the party said on Sunday evening.
Kumalo, 71, was first deployed to the United Nations in 1999 and returned home a decade later following the country's successful tenure as a non-permanent member of the Security Council, said the ANC in a statement.
The ANC said Kumalo served the country "diligently" as the country's diplomat to the United Nations (UN).
"Forced into exile for his anti-apartheid activities and while on asylum in the United States, he continued his political activity as a project director at the American Committee on Africa (ACOA) and its sister organisation, the Africa Fund from 1979 to 1997, playing a key role in the mobilisation of American sanctions against the racist apartheid regime. Kumalo's actions culminated in the racist regime being hauled to the UN Security Council in the 80s," the party said.
Kumalo distinguished himself as a diplomat par excellence when the consolidation of the African Agenda found expression in the multilateral sphere which entailed a report on how the UN could assist the African continent in the resolution of conflicts, the ANC said.
"The ANC dips its revolutionary flag and extends its condolences to the family, friends, as well as to his fellow comrades in the struggle for liberation of the oppressed," the ANC said.