Floods have killed 42 people in central and eastern Europe since last month and forced around 40,000 others to flee their homes, the United Nations said Tuesday.

Heavy rains and storms have led to some of the worst floods in 40 years in parts of Ukraine, Moldova and Romania since July 22, causing great damage to homes, infrastructure and farmland, said Elisabeth Byrs, spokeswoman for the UN's Office for the Coordination of Humanitarian Affairs (OCHA).

In Ukraine, 34 people have been killed in the west of the country along the Dnestr and Prut rivers while over 25,000 others have been evacuated.

A total of 24,000 hectares of farmland is still flooded, and a significant part of the potato, root crops and vegetable harvest in local farms has been damaged, Byrs warned.

Some parts of western Ukraine have been cut off by road due to the flooding so food and water have to be delivered by helicopter, she added.

In Moldova, three people are reported to have drowned in the capital Chisinau while 4,251 people have been evacuated and 836 houses flooded.

Romania meanwhile has seen some of the worst flooding for four decades with five people killed, 10,520 evacuated and 8,941 houses damaged, Byrs said.