A tropical cyclone was moving on Monday toward Mozambique, where about 40 people have already died in flooding caused by heavy rains and 18 000 people have fled to emergency shelters.
Cyclone Flavio, located on Monday morning in the Mozambique Channel about 200km off the coast, was moving inland at a rate of 12kph, South African public radio reported.
Expected heavy rains and strong winds were likely to hamper relief efforts in the centre of the country, through which the Zambezi River and its tributaries flow.
About 85 000 people in the region have evacuated their homes over the past few weeks as dangerously high water levels in the Cahora Bassa dam on the Zambezi River necessitated hefty discharges of water into the surrounding valley.
Vast stretches of land have been submerged by floodwaters and thousands of homes destroyed.
The cyclone was expected to hit by Thursday morning around Gaza, Inhambane and Sofala.
The Mozambican government said the situation was largely under control but emergency supplies were urgently needed as the situation looked unlikely to improve for weeks.
Angola, Zambia and Malawi have also been affected by recent flooding. – Sapa-DPA