Floods subsided across Sri Lanka Tuesday revealing the full extent of damage from last week's deluge that also triggered landslides, officials said, as the death toll crossed 100.

The Disaster Management Centre (DMC) said 101 people were known to have died last week while another 100 people were still listed as missing in the worst hit central district of Kegalle.

Military officials in the district, 100 kilometres (60 miles) north-east of the capital, said a search was still under way for the missing people although there was little hope of finding anyone alive under the tonnes of mud.

"The flood waters have receded across the country," DMC spokesman Pradeep Kodippili told AFP. "Over 530 houses have been completely destroyed and another 4,000 partly damaged."

He said most of the capital's flood-affected population had returned to their homes since Monday when the water levels started going down.

At the height of the floods, a third of Colombo's 650,000 residents were driven out of their homes, according to official figures.

The Finance Ministry has estimated the damage to small businesses and industries at about $2 billion. The government has promised compensation to victims, but details are yet to be announced.

Sri Lanka's parliament has been recalled to meet Wednesday, a week ahead of schedule, to discuss reconstruction and rehabilitation following the worst flooding in the capital in nearly a quarter of a century.

Soldiers and relief workers were seen distributing essential supplies to people cleaning up their homes in low-lying areas of Colombo.

Floodwaters from the Kelani, which flows to the Indian Ocean through Colombo, were contaminated with garbage from a dump on the edge of the city as well as raw sewage, raising concerns of a disease outbreak, officials said.

Doctors and nurses were seen across the affected areas Tuesday while the authorities maintained mobile medical units.

Sri Lanka has received international aid as well as support from nationals keen to help the victims.

Rain has eased since Cyclone Roanu moved away from Sri Lanka to hit southern Bangladesh on Saturday, leaving at least 24 people dead there, before weakening.