The number known to have died has risen in Germany and Belgium after heavy rain caused rivers to burst their banks, sweeping away homes and cars.
Europe has been battered by days of torrential rain and floods that have left more than 160 people dead and hundreds more injured.
By Saturday, waters were receding across much of the affected regions, but officials feared that more bodies might be found in cars and trucks that were swept away.
Germany has borne the brunt of the extreme weather, with at least 141 people killed in two states.
Belgium’s national crisis centre said the country's confirmed death toll rose to 27.
German President Frank-Walter Steinmeier travelled to Erftstadt in the state of North Rhine-Westphalia, where a massive rescue effort unfolded on Friday.
“A lot of people have lost everything they spent their lives building up — their possessions, their home, the roof over their heads,” Steinmeier said.
“It may only be possible to clear up in weeks how much damage needs to be compensated,” he said.
Many areas were still without electricity and telephone service — something that appeared to have accounted in part for large numbers of missing people that authorities gave immediately after the floods hit on Wednesday and Thursday.
Costly rebuilding ahead
Visiting Erftstadt with Steinmeier, North Rhine-Westphalia governor Armin Laschet promised to organise aid for those immediately affected “in the coming days.”
He said authorities would discuss in the coming days how to support rebuilding efforts. Chancellor Angela Merkel's Cabinet plans to discuss the issue on Wednesday.
“We will do everything so that what needs to be rebuilt can be rebuilt,” Laschet said.
Across the border in eastern Belgium, train lines and roads remained blocked in many areas.
Belgian Prime Minister Alexander De Croo and European Commission President Ursula von der Leyen were visiting the country's most affected regions on Saturday morning.
"My heart sank when I met people who lost their homes and the savings of a lifetime. I told them: Europe is with you. We share your grief. We will help you rebuild," von der Leyen tweeted.
Southern parts of the Netherlands also have been hit by heavy flooding.
Thousands of residents were allowed to return home Saturday morning after being evacuated on Thursday and Friday.
Caretaker Prime Minister Mark Rutte, who visited the region on Friday, said that “first, there was corona, now these floods, and soon people will have to work on cleanup and recovery.”
His government has declared the flooding a state of emergency, opening up national funds for those affected.
France and Switzerland have also been hit by flooding, the worst parts of Europe have seen in living memory.
There are many questions to answer after such unprecedented flooding including what went wrong with the warning system.
Many are also blaming it on climate change.
But on Thursday Armin Laschet, the state premier who is tipped to replace Chancellor Angela Merkel said in a TV interview that he wouldn't change environmental policy because of one natural disaster.
Speaking from Washington, Chancellor Angela Merkel said in a statement that she was "shocked by the catastrophe that so many people in the flood areas have to endure".
"My sympathy goes out to the families of the dead and missing. My heartfelt thanks go to the many tireless helpers and emergency services," she added.
Steinmeier said that fighting climate change was the only way of preventing natural disasters on this scale from happening more often.
Speaking Friday, Steinmeier said he had spoken to regional leaders in the areas of Germany most badly affected by the flooding, and that they had described "harrowing" conditions on the ground.
'Reduced to rubble'
On Thursday, large parts of Germany were completely cut off, with telephone and internet down and authorities warning that the 112 emergency number was "not reachable".
Earlier, dozens of people were reported missing after several homes collapsed in the village of Schuld in the Eifel, a volcanic region of rolling hills and small valleys.
Many villages were reduced to rubble as old brick and timber houses couldn't withstand the sudden rush of water, often carrying trees and other debris as it gushed through narrow streets.
This video shows submerged cars in Uxheim, also in Rhineland-Palatinate on July 14. Subsequent footage reveals the scene the following day.
Meanwhile, this was a rescue operation in Trier, further south from Uxheim.
The governor of Rhineland-Palatinate state, Malu Dreyer, told the regional parliament on Thursday that "We have never seen such a disaster. It's really devastating."
European Commission chief Ursula von der Leyen wrote on Twitter that the bloc "is ready to help" and that countries impacted by the floods can call on the EU Civil Protection Mechanism.
"My thoughts are with the families of the victims of the devastating floods in Belgium, Germany, Luxembourg, and the Netherlands and with those who have lost their homes."
European states had already worked together to deal with the crisis with Italy and Austria offering flood rescue teams to Belgium, while the EU's Copernicus emergency satellite mapping is providing assessment maps of the affected areas.
France dispatched a team of 40 rescuers to Belgium on Thursday as well as a search and rescue helicopter and on Friday offered to send soldiers to Germany.
"France is showing solidarity," President Emmanuel Macron wrote on Twitter on Friday. "Our support is already deployed in Belgium. It will be deployed wherever it is useful."
Dozens of people had to be rescued from the roofs of their houses with inflatable boats and helicopters. Hundreds of soldiers were deployed to assist in the rescue efforts.
“There are people dead, there are people missing, there are many who are still in danger,” the governor of Rhineland-Palatinate state, Malu Dreyer, told the regional parliament. “We have never seen such a disaster. It’s really devastating.”
In the Netherlands, soldiers were dispatched to transport evacuees and fill sandbags as rivers burst their banks.
Stefan Rahmstorf, a professor of ocean physics at the Potsdam Institute for Climate Impact Research, said it was unclear whether the extreme rainfall seen in Germany was a direct result of planetary warming.
“But one can state that such events are becoming more frequent due to global warming,” he told The Associated Press, noting that warmer air can absorb more water vapor that eventually falls as rain.
“The increase in heavy rain and decrease in days with weak rain is now also clearly seen in observational data, especially in the mid-northern latitudes, which includes Germany,” Rahmstorf said.
The weakening of the summer circulation of the atmosphere, causing longer-lasting weather patterns such as heatwaves or continuous rain, might also play a role, he added.