The death toll from Ukraine's worst floods in 200 years climbed to 30 on Thursday, as three people were also found dead in neighbouring Moldova, the authorities said.

"Thirty people have been killed: 23 drowned, three were struck by lightning, three were electrocuted and one died in a landslide," emergency situations minister Vladimir Shandra told parliament.

The previous toll stood at 22 dead, with almost 20,000 people evacuated.

Records showed the recent floods were the worst in 200 years, Shandra told parliament.

In the Moldovan capital Chisinau, three people were found dead Thursday after being swept away by floodwaters, an interior ministry spokeswoman said.

Two drowned when they became trapped under cars while trying to cross a flooded road. Another was found under a bridge.

More than 100 houses had been destroyed in the storms and more than 5,000 people evacuated, the spokeswoman said.

Earlier this week authorities in Romania said four people died and more than 11,000 people had been evacuated from their homes in the north of the country because of flooding.

The Russian Prime Minister Vladimir Putin has ordered humanitarian aid to be sent to the victims, the Ria Novosti news agency said Thursday.