The 15-member UN Security Council met on Tuesday at the request of both Russia and Ukraine after a torrent of water burst through a massive dam on the Dnipro River that separates the opposing forces in southern Ukraine.
When asked if the United States knew who was responsible, Deputy US Ambassador to the United Nations, Robert Wood, told reporters ahead of the council meeting: "We're not certain at all, we hope to have more information in the coming days."
"But, I mean, come on ... why would Ukraine do this to its own territory and people, flood its land, force tens of thousands of people to leave their homes - it doesn't make sense," Wood said.
UN Secretary-General Antonio Guterres said earlier on Tuesday that the world body did not have any independent information on how the dam burst, but described it as "another devastating consequence of the Russian invasion of Ukraine."
Many Security Council members also asserted during Tuesday's meeting that the crisis would not have occurred if Russia had not invaded neighbouring Ukraine in February last year.
Russia's UN Ambassador Vassily Nebenzia blamed Ukraine, without providing evidence, accusing it of trying to create "favourable opportunities" for it to regroup its military units to continue a counter-offensive.
"The deliberate sabotage undertaken by Kyiv against a critical infrastructure facility is extremely dangerous and can essentially be classified as a war crime or an act of terrorism," Nebenzia told the council.
Ukraine's UN Ambassador Sergiy Kyslytsya accused Russia of a "terrorist act against Ukrainian critical infrastructure," without providing evidence.
"It is physically impossible to blow it up somehow from the outside by shelling - it was mined by the Russian occupiers and they blew it up," Kyslytsya said.
UN aid chief Martin Griffiths told the Security Council that "the sheer magnitude of the catastrophe will only become fully realized in the coming days."
"But it's already clear that it will have grave and far-reaching consequences for thousands of people in southern Ukraine on both sides of the front line through the loss of homes, food, safe water and livelihoods," he added.
Ukraine's Zelenskiy says dam bursting is 'environmental bomb of mass destruction'
President Volodymyr Zelenskiy described the bursting of the Kakhovka dam in southern Ukraine on Tuesday as "an environmental bomb of mass destruction" and said only liberating the entire country could guarantee against new "terrorist" acts.
"Such deliberate destruction by the Russian occupiers and other structures of the hydroelectric power station is an environmental bomb of mass destruction," Zelenskiy said in his nightly video address.
Zelenskiy said the destruction of the dam would "not stop Ukraine and Ukrainians. We will still liberate all our land.
"Only the complete liberation of Ukrainian land from the Russian occupiers will guarantee that there will be no more such terrorist attacks."
Hundreds of people have been evacuated from settlements along the southern stretch of Ukraine's Dnipro River as flood waters submerged streets, town squares and homes.
The Kremlin blamed Ukraine, saying it was trying to distract from the launch of a major counteroffensive Moscow says is faltering.
Some Russian-installed officials said the dam had collapsed on its own.
Destruction of Kakhovka dam helps Russian defence against Ukrainian counteroffensive, says security expert
The destruction of the Nova Kakhovka dam in southern Ukraine has improved the defensive positions of Russian troops against a much-awaited Ukrainian counteroffensive, a security expert said on Tuesday.
The flooding caused by the breach of the huge dam on the front-line Dnipro River could prevent Ukraine from deploying heavy weaponry such as tanks in the area for up to a month, said Maciej Matysiak, a security expert at the Stratpoints Foundation and ex-deputy chief of Polish military counter-intelligence.
"But at the same time, it covers for Ukrainians' safety, on this flank because during (the) expected offensive of (the) Ukrainian army, Russians won't be able to operate in this direction, ” Matysiak added.
Marina Miron, a researcher at King's College in London, called it a "turning point" in the war but said both sides could see some advantage in blowing up the dam.
"For Russians the reason to do it would have been to stop the Ukrainian counteroffensive, obviously. And to create a humanitarian situation in Kherson, where people need to be evacuated and to create swamps so that Ukrainians would not be able to use their mechanized infantry, for instance," she said.
For Ukraine, the breach might have provided a way of distracting the Russians while Kyiv launches its counteroffensive, she added.
The breach of the dam in Ukraine's Kherson region on Tuesday has muddied the picture for the anticipated Ukrainian counteroffensive and threatens an environmental disaster for civilians living in the war zone.
Kyiv and Moscow have blamed each other for the collapse of the dam that sent floods gushing towards surrounding towns and farmland and forced hundreds of civilians to flee.
Civilians worry for homes as floods spread in wake of dam breach
Hundreds of people were evacuated from settlements along the southern stretch of Ukraine's Dnipro river as flood waters submerged streets and town squares, leaving civilians worried for their homes in Kherson on Tuesday.
Oleksandr Reva, a local resident, told Reuters: "The situation is literally critical. If the water raises for another metre, we will lose our house. We are moving our stuff now to the neighbours who live on higher ground. They moved and left the house so we can bring our stuff and stay there. We are trying to save our most valuable belongings.”
Residents with pets and suitcases walked on flooded streets, waiting to be evacuated.
A torrent of water burst through a massive dam on the Dnipro River that separates Russian and Ukrainian forces in southern Ukraine on Tuesday, flooding a swathe of the war zone, forcing villagers to flee and prompting finger-pointing from both sides.
The dam supplies water to a wide area of southern Ukrainian farmland, including the Russian-occupied Crimean peninsula, as well as cooling the Russian-held Zaporizhzhia nuclear plant.