The International Federation of Red Cross and Red Crescent societies said in a statement that medical supplies and infrastructure were severely damaged by major flooding across five provinces and the health situation was worsening.

"We have at least 89,000 people left completely homeless after this disaster and we are working hard to respond to their needs," said Jaap Timmer, head of the Federation's delegation in North Korea.

"But with clinics and hospitals put out of action and drug supplies ruined, the number of people whose lives have been impacted is far wider, and they need the international community's help," he added.

"The situation is worsening as people are falling sick due to the poor hygiene conditions."

The appeal is mainly aimed at providing basic emergency medicines in the two worst-affected provinces, South Hamgyong and South Phyongan, and in the city of Kaesong, where most of the 3.7 million people in need live, federation spokeswoman Anna Nelson told AFP.

About half of the displaced families in the country do not have access to clean drinking water and cases of watery diarrhoea have reportedly increased by 20 percent, she added.

The federation said the heaviest rains in 40 years over the past two weeks completely or partially destroyed 30 to 40 percent of health facilities and supplies in North Korea, as well as homes, roads and crops.

There were also reports of an increase in acute respiratory infections, particularly in children, dehydration and skin and eye infections, the agency said.