Ukrainian troops have continued their incursion into Russia’s western Kursk region on Friday night.
Russian defence ministry claims it was repelling the Ukraine military but reports indicate Ukrainian troops are operating more than 10km (six miles) inside Russia.
Although Ukraine has not openly admitted the incursion, its President Volodymyr Zelensky said on Thursday that Moscow must “feel” the consequences of its actions.
Fighting between the two countries in Kursk has edged gradually closer to a nuclear power plant, prompting the UN nuclear agency to release a statement urging the two sides to “exercise maximum restraint”.
International Atomic Energy Agency (IAEA) chief Rafael Grossi appealed to all sides to take measures “to avoid a nuclear accident with the potential for serious radiological consequences”.