Heavy Shelling Reported In Donetsk Region As Ukrainian Forces Make Gains In Kherson.

Ukrainian soldiers fire toward Russian troops at a position in the Donetsk region on August 12.

Heavy shelling by Russian forces in the eastern Ukrainian region of Donetsk was reported overnight, with officials in Kyiv saying they are managing to repel many of the attacks while recapturing ground in the southern Kherson region.

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President Volodymyr Zelenskiy said in his overnight address late on August 14 that despite the heavy and constant bombardment by Russian forces, "We must fight at all levels and on all fronts, strengthen our state as much as possible, preserve our unity, and attract even more countries to our anti-war coalition.

"The stronger Ukraine will be, the weaker Russia will be, and therefore, the less time this war will last," he said in the address, noting Kyiv is pushing for new sanctions against Russia by the international community, especially ones that target the movement of Russian citizens.

For several weeks, Ukraine's military has tried to lay the groundwork for a counteroffensive to reclaim southern Ukraine's Kherson region, which borders Crimea and fell to the Russians soon after the February 24 invasion.

Particularly heavy fighting has focused on the village of Pisky, near Donetsk Airport, according to the British Defense Ministry, which said on August 15 that it is likely Moscow is in the advanced planning stages to hold a referendum aimed at making the region part of Russia, "though it is unclear if the final decision to go ahead with a vote has yet been taken."

"The Kremlin will likely see the military’s failure to occupy the entirety of Donetsk Oblast thus far as a setback for its maximalist objectives in Ukraine," it said in a daily statement on Twitter.

Meanwhile, the situation at the Zaporizhzhya nuclear power plant -- Europe's largest nuclear power station -- continues to be a source of major concern for the international community.

Zelenskiy warned over the weekend that recent shelling at the plant has increased the threat of a leak of radiation.

Russia doesn't deny it has troops located at the plant but has disputed claims it has shelled the area. Instead, Moscow blames Ukrainian forces for firing artillery shells in the area, which officials in Kyiv deny.

While the plant is controlled by Russia, its Ukrainian staff continues to run the nuclear operations. It is in Enerhodar, a city seized by Russian troops in early March soon after they invaded Ukraine on February 24.

"Deployment of Russian military personnel and weaponry at the nuclear facility is unacceptable and disregards the safety, security, and safeguards principles that all members of the IAEA have committed to respect," a statement by 42 nations worldwide that was published by the European Union on August 14 said.

With reporting by AFP and Reuters