The United Nations atomic watchdog chief has condemned what he described as targeted attacks on the Russian-occupied Zaporizhzhia nuclear plant in Ukraine, calling for a “stop to this madness”.

Powerful explosions from shelling shook Ukraine’s Zaporizhia region, the site of Europe’s largest nuclear power plant, over the weekend.

A heavy barrage of Russian military attacks — almost 400 on Sunday alone — also hit Ukraine’s eastern regions, and fierce ground battles were underway in eastern Donetsk province, Ukraine’s President Volodymyr Zelenskyy said in his evening update on Sunday.

“The news from our team yesterday and this morning is extremely disturbing,” Rafael Grossi, head of the International Atomic Energy Agency (IAEA), said in a statement on Sunday.

“Explosions occurred at the site of this major nuclear power plant, which is completely unacceptable.

“Whoever is behind this, it must stop immediately,” he added.

“As I have said many times before, you’re playing with fire!”

In renewed shelling close to and at the site, IAEA experts at the Zaporizhzhia facility reported hearing more than a dozen blasts within a short period on Sunday morning and could see some explosions from their windows, the agency said.

Later in the day, the IAEA said the shelling had stopped and that its experts would assess the situation on Monday.

“There has been damage to parts of the site, but no radiation release or loss of power,” it said.

Speaking to a French broadcaster, Grossi said it was clear that the raids on the plant were no accident.

“The people who are doing this know where they are hitting. It is absolutely deliberate, targeted.”

Attacks in and around Zaporizhzhia have raised the risk of a nuclear catastrophe at the plant, which Russia occupied shortly after invading Ukraine on February 24.

Blackouts

Russia has been pounding Ukraine’s power grid and other critical civilian infrastructure from the air, causing widespread blackouts and leaving millions of Ukrainians without heat, power or water as temperatures plunge and snow begins to fall in the capital, Kyiv, and other cities.

Ukraine’s state nuclear power operator, Energoatom, blamed Russian forces for the latest shelling of Zaporizhzhia and said the equipment targeted was consistent with the Kremlin’s intent “to damage or destroy as much of Ukraine’s energy infrastructure as possible” as the winter sets in.

Moscow, meanwhile, has blamed Ukrainian forces for the damage.

Russian Defence Ministry Spokesperson Igor Konashenkov accused the Ukrainians of shelling the power plant twice on Sunday and said two shells hit near power lines supplying the plant with electricity.

Ukraine has said work is continuing to repair damage to the country’s energy infrastructure but “stabilisation blackouts” would be necessary in 15 regions, including the capital on Sunday night. The country’s power utility said there would be scheduled outages in every region on Monday.

“The restoration of networks and technical supply capabilities, the de-mining of power transmission lines, repairs — everything goes on round the clock,” Zelenskyy said in his nightly address.

Many cities are suffering power shortages after Russian attacks on major infrastructure [Valentyn Ogirenko/Reuters]

Zelenskyy said Ukrainian forces were making small gains in the eastern Luhansk region and were holding their ground in battles in the south.

Russia withdrew its forces from the southern city of Kherson this month and moved some of them to reinforce positions in the east.

“The fiercest battles, as before, are in the Donetsk region. Although there were fewer attacks today due to worsening weather, the amount of Russian shelling unfortunately remains extremely high,” Zelenskyy said.

In the address, the president again set out Kyiv’s terms for peace, including food and energy security, the release of all prisoners and deportees, and the withdrawal of Russian troops from all Ukrainian territory. (Al JAzeera)

•PHOTO: Ukrainian soldiers fire artillery at Russian positions near Bakhmut, Donetsk region, Ukraine, Sunday, November 20, 2022. (AP Photo/LIBKOS)

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