The United Nations does not have any independent information on how a Ukrainian dam burst, U.N. Secretary-General Antonio Guterres said on Tuesday, describing it as "another devastating consequence of the Russian invasion of Ukraine."
The U.N. Security Council will meet later on Tuesday to discuss the dam at the request of both Russia and Ukraine.
"Attacks against civilians and critical civilian infrastructure must stop. We must act to ensure accountability and respect for international humanitarian law," Guterres told reporters.
A torrent of water burst through a massive dam on the Dnipro River that separates Russian and Ukrainian forces in southern Ukraine, flooding a swathe of the war zone and forcing villagers to flee.
According to the Security Council meeting requests seen by Reuters, Ukraine accused Russia of an "ecological and technological act of terrorism", while Russia described it as an "act of sabotage carried out by Ukraine."
Guterres said it was a "monumental humanitarian, economic and ecological catastrophe."
"At least 16,000 people have already lost their homes - with safe and clean drinking water supplies at risk for many thousands more," he said, adding that the United Nations was coordinating with the Ukrainian government to send support including drinking water and water purification tablets.
(Reporting by Michelle Nichols; editing by Rami Ayyub and David Gregorio)