The government said hundreds of villagers will remain homeless if authorities decide to open the spillway gates of the dam -- one of the world's largest -- to prevent its walls from cracking. Doing so could affect power generation.

The government said it had started evacuating people living on the banks of three major rivers already battered by regional floods which have killed dozens and left thousands homeless in Zambia, Zimbabwe and Malawi.

So far floods have killed six people in southern Zambia.

The financial costs could also be high. Kariba Dam supplies power to Zambia's Copperbelt, its industrial base and the economy's lifeblood.

Zambian state television showed footage of police picking up a sixth flooding victim from the Maramba stream in Livingstone.

Officials said the spillway gates of another dam, the Itezhi-Tezhi, may also be opened, possibly displacing thousands of villagers living along the banks of the Kafue, Luangwa and Zambezi rivers.

"Further outlook indicates that more rains are expected in the future, especially during February/March, which is the peak period," said the Zambezi River Authority.

Vice President Rupiah Banda said on state television that government officials had started telling people living along river banks to abandon their homes.

Banda said the government was also preparing relief operations as most maize fields in eastern Zambia were expected to be washed away by flood waters from dams.

"We are moving tents to people that will need them and we will provide relief maize because some people will lose their maize when the spillway gates are opened," Banda said.