Speaking at a Department of Agriculture, Forestry and Fisheries (DAFF) media briefing in Pretoria, Minister Senzeni Zokwana said about 260 000 birds had already been culled following an avian influenza outbreak on two farms in Mpumalanga.
The affected farms, an egg producer and a broiler producer, have been placed under quarantine.
According to DAFF animal health director, Dr Mpho Maja, neighbouring countries suspended live imports from South Africa, but as the disease did not affect humans, processed products were still being exported.
The ban would be upheld until DAFF was convinced all proper processes had been followed, Zokwana said.
The disease was spread by wild migratory birds from Europe.
Free-range farmers have been advised to remove feed and water that could be accessed by these wild birds, Zokwana said.