Ukraine said Monday it has launched a counteroffensive to try to retake territory in the southern part of the country that Russia seized in the earliest weeks of its six-month invasion.

“Today we started offensive actions in various directions, including in the Kherson region,” Ukrainian public broadcaster Suspilne reported, quoting southern command spokeswoman Natalia Humeniuk.

Russia failed to capture the capital, Kyiv, in northern Ukraine in its initial attack, but took control of wide swathes of land in the south along the Black Sea coast.

Fighting for months has centered on eastern Ukraine in the Donbas region, where Russia-supported separatists and Kyiv’s forces have fought since 2014, the same year Moscow seized Ukraine’s Crimean Peninsula, although the international community has not universally recognized the Russian takeover.

The conflict in eastern Ukraine has been at somewhat of a standstill for weeks, with Russia and Ukraine gaining or losing territory incrementally.

But Western allies, led by the United States, have continued to ship armaments to the Kyiv government, possibly giving Ukraine new confidence to further attack in the southern reaches of the country.

The battlefield strategy came as the head of the U.N. atomic energy agency said it has a team on the way to visit Ukraine’s Zaporizhzhia nuclear power plant, situated near the front line of Russia’s invasion of Ukraine.

International Atomic Energy Agency Director-General Rafael Mariano Grossi tweeted that he is leading the team that will be at the power plant “later this week.”

“We must protect the safety and security of Ukraine’s and Europe’s biggest nuclear facility,” Grossi said.

The IAEA said the mission will focus on assessing physical damage at the plant, determining the functionality of safety and security systems, evaluating staff conditions and performing “urgent safeguards” activity.

Russia has controlled the plant site since early in its invasion, but the plant is being operated by Ukrainian engineers.

Ukrainian Foreign Minister Dmytro Kuleba told reporters Monday in Stockholm that the international community should be united in demanding Russia’s withdrawal from the nuclear plant, saying that is the only way to ensure security at the site.

“We expect from the mission a clear statement of facts of [the] violation of nuclear safety protocols. We know that Russia is putting not only Ukraine but also [the] entire world at threat, at risk of [a] nuclear accident,” Kuleba said.

Despite numerous attacks in the area that Russia and Ukraine have blamed on each other, Grossi said Ukraine has told the agency that “all safety systems remained operational and there had been no increase in radiation levels.”

Russia launched new rocket and artillery attacks near the facility early Sunday, with Ukrainian officials reporting significant damage.

Ukraine’s Valentyn Reznichenko, governor of the Dnipropetrovsk region, said that heavy firing during the night left parts of Nikopol, about 10 kilometers from the nuclear site, without electricity. Rocket strikes damaged about a dozen homes in another nearby city, Marhanets.

The city of Zaporizhzhia, about 40 kilometers upriver from the nuclear facility, was also attacked, with city council member Anatoliy Kurtev saying two people were injured.

Russian Defense Ministry spokesman Igor Konashenkov claimed Sunday that shells fired by Ukrainian forces fell near buildings storing reactor fuel and radioactive waste.

The U.S. State Department accused Russia of blocking a consensus document on a nuclear non-proliferation treaty because the agreement noted the risk posed by fighting near the Zaporizhzhia plant.

“For the Russian Federation to not accept such language in the face of overwhelming international consensus underscores the need for the United States and others to continue urging Russia to end its military activity near ZNPP and return control of the plant to Ukraine,” the statement said.

Moscow said it supports the work of the IAEA but has refused to withdraw its soldiers from the complex to create a demilitarized zone.

An engineer working under Russian occupation since March 4 at the Zaporizhzhia power plant has told VOA that Russian forces have placed artillery and missile installations within and around the property.

The engineer, whose identity is being withheld for fear of retaliation by the occupying authorities, supports Ukrainian government claims that Russia itself is responsible for the explosions.

Some information for this story came from The Associated Press, Agence France-Presse and Reuters.