Ukrainian President Volodymyr Zelenskiy accused Russian forces on Tuesday of blowing up the Kakhovka Hydroelectric Power Station after mining the facility, and said Moscow must be held to account for a "terrorist attack".
A Ukrainian military spokesperson said Russia's aim was to prevent Ukrainian troops crossing the Dnipro river to attack Russian occupying forces.
Russian-installed officials gave conflicting accounts, some blaming Ukrainian shelling, others saying the dam on the Dnipro had burst on its own.
"Tonight at 02:50, Russian terrorists carried out an internal detonation of the structures of the Kakhovskaya HPP (hydroelectric power plant)," Zelenskiy said after an emergency meeting of senior officials.
He said "a set of international and security measures was agreed upon (at the meeting) to hold Russia accountable for this terrorist attack."
In a later video address to a summit of European countries in the Bucharest Nine group, Zelenskiy said Russia had controlled the dam and hydroelectric plant for over a year.
"It is physically impossible to blow it up somehow from the outside - with shelling. It was mined. It was mined by the Russian occupiers and blown up by them," he said.
Zelenskiy, whose country wants to join NATO, urged members of the military alliance meeting in Vilnius next month to show "there will be no weakness in Europe" and demonstrate to Russia that "terror is not a tool to influence NATO's decisions".
The Foreign Ministry called for an urgent U.N. Security Council meeting and new sanctions on Russia, in particular on its missile industry and nuclear sector.
Serhiy Naev, commander of the joint forces of the Armed Forces of Ukraine, said the dam's destruction "should not prevent our advance in those directions where there may be spillage of water."
(Reporting by Dan Peleschuk and Olena Harmash, Editing by Timothy Heritage)