The session was requested by British Prime Minister Boris Johnson, diplomats told AFP, with the United States, France, Norway, Ireland and Albania joining the call for an urgent meeting.

Western leaders had expressed horror Friday after the Zaporizhzhia plant in southern Ukraine was attacked with shell fire and taken over by invading Russian forces.

The six reactors at Zaporizhzhia, which can power enough energy for four million homes, were apparently undamaged and international monitors reported no spike in radiation.

British Foreign Secretary Liz Truss called for the Security Council session while in Brussels for a NATO foreign ministers' meeting.

The attack was "a threat to European security and stability and we need those responsible to be held to account," she told British television on the sidelines of the meeting.