Rescuers scrambled on Wednesday to reach survivors in Malawi's battered city of Blantyre, after Cyclone Freddy struck southern Africa for a second time, triggering floods and landslides that have killed more than 200 people.

Weather conditions were expected to improve as the storm dissipated over land after days of torrential rains, but localised thunderstorms would persist, and flood levels remained high in some areas, hampering emergency efforts.

"We found people in the trees, on rooftops or on higher grounds," Red Cross Malawi spokesman Felix Washoni told AFP.

"It's a challenge to reach them, water is high, and bridges are broken."

Freddy returned to southeastern Africa at the weekend for a second time in less than three weeks, leaving behind a trail of death and destruction.

At least 190 people were killed in Malawi with 584 injured and 37 missing. The authorities in neighbouring Mozambique reported 21 deaths.

Pope Francis offered prayers for the Malawi cyclone victims, during his weekly audience at St Peter's Square.

"I pray for the dead, the injured, the displaced. May the Lord support the families and the communities hardest hit by this calamity," he said.

- Hope fading -

Rescue workers warned that more victims were to be expected as they scoured destroyed neighbourhoods for survivors, even as hopes dwindled.

"Four people from my family are still missing as they are buried in the mud," Alabu Wiseman, 24, said from a Blantyre school-turned-temporary-shelter.

The army and police were leading search and rescue operations, which the Red Cross said would continue for at least another two days.

Many people perished in mudslides that washed away homes in Blantyre, the country's commercial capital.

Across Malawi, nearly 59,000 people have been affected and more than 19,000 displaced, with many now sheltering in schools and churches.

Authorities counted at least a dozen clinics now accessible due to floods or damaged roads.

The impoverished country is already grappling with the deadliest cholera outbreak in its history, which has killed over 1,600 people since last year.

On Wednesday, markets and shops were re-opening in Blantyre.

"I have two young daughters to feed," Daud Chitumba, 27, a minibus conductor told AFP as he headed to work at a local bus depot.

His house was among dozens swept away by a mudslide in the township of Chilobwe.

"We have to rebuild our lives and it starts with picking up the small pieces. So, I have to... try to do whatever I can to move forward," Chitumba said.

- 'Devastated nation' -

President Lazarus Chakwera, who returned to Malawi on Tuesday after attending a UN conference in Qatar, was due to visit affected areas on Wednesday.

"We have arrived to a devastated nation," he said in a statement, hailing the relief efforts by volunteers.

Some said that government assistance has been slow in coming.

"We feel abandoned here," said Fadila Njolomole, 19.

"Just yesterday, we lost two more people who went with the mudslide as they helped to dig up the bodies. People are hungry and tired.

"My best friend, her brother, sister and mother went with the mudslide and their bodies have not been found. It's devastating. You can't even mourn."

Cyclone Freddy smashed into landlocked Malawi early Monday after sweeping through Mozambique at the weekend but the tally was expected to rise.

"We're still at an early stage...of tallying up the full impact of this cyclone," said UNICEF Mozambique spokesman Guy Taylor, adding that the toll "will probably increase".

The storm has unofficially broken the World Meteorological Organization's benchmark as the longest-lasting tropical cyclone on record, set in 1994 for a 31-day storm named John.

Cyclone Freddy swirled for more 35 days.

Freddy became a named storm on February 6, making landfall in Madagascar on February 21 and sweeping over the island before reaching Mozambique on February 24.

It then returned to the Indian Ocean and gathered new force over the warm waters, then reversed course to come back much more powerful, packing wind gusts of up to 200 kilometres per hour (125 mph).

Cyclones tracking across the entire Indian Ocean are very infrequent, say meteorologists -- the last occurred in 2000.