Russia on Sunday shelled the center of Kherson, the southern Ukrainian city it retreated from last month, in the latest in a barrage of attacks on the region.

Three people were wounded in the assault on Kherson, one Ukrainian official said, while the regional governor, Yaroslav Yanushevych, said that Russia in the past day had launched 54 attacks with rocket, mortar and tank fire in the Kherson area, killing three people and wounding six.

Meanwhile, in Russia, Vyacheslav Gladkov, the governor of the Belgorod region, said Sunday that one person was killed and eight others wounded in Ukrainian shelling of the area, which lies along Ukraine’s northern border.

For weeks, Russia has been targeting Ukrainian infrastructure as winter sets in, attempting to knock out water and electricity supply lines to demoralize the Ukrainian population.

Rolling blackouts have hit much of the country, but Ukrainian President Volodymyr Zelenskyy said in his nightly video address on Saturday that power has been restored to almost 6 million Ukrainians. He said crews have been working nonstop to stabilize the energy grid to restore heat and water supplies.

The most difficult situation, he said, is in “Kyiv and the region, Vinnytsia and the region, Lviv and the region.” But large-scale power outages are affecting many other regions, as well, including Dnipro and Dnipropetrovsk.

Oksana Markarova, Ukraine’s ambassador to the United States, told ABC News’s “This Week” show, “We see what happens when we don’t have enough air defense.”

Markarova said half of Ukraine’s energy grid has been destroyed by Russian missiles. “We have to stop it. And the only way to do it is with increased number of air defense everywhere in Ukraine,” she said.

U.S. officials say they are planning to send a Patriot missile air defense battery to Ukraine to help shoot down incoming Russian airstrikes, but no official announcement has been made. Russia has condemned the anticipated U.S. action and called it a provocation heightening U.S. involvement in the conflict.

Ukrainian soldiers rest near their position in Bakhmut, Donetsk region, Ukraine, Dec. 17, 2022.

Ukrainian soldiers rest near their position in Bakhmut, Donetsk region, Ukraine, Dec. 17, 2022.

Nonetheless, the United States will provide additional security assistance to Ukraine, National Security Council spokesman John Kirby told VOA in an interview on Friday.

Asked if Washington would heed Russia’s warning not to deliver sophisticated Patriot air defense missiles or risk the consequences, Kirby replied, “Russia will not dictate to the United States or any other country what security assistance we provide to Ukraine.”

The U.S. official said Washington is in “lockstep with the Ukrainians, talking to them almost every day about what their needs are, and making sure that we are best meeting those needs.”

Zelenskyy thanked the European Union and United States for decisions to provide defense, energy and financial support to Ukraine in the coming year. He added there is more to be done and urged “a reliable air defense shield,” that will protect the Ukrainian people from “the main form of Russian terror – missile terror.”

In an intelligence update Saturday, Britain’s Defense Ministry said, “In recent days, there has been an uptick in Russia’s campaign of long-range strikes against Ukraine’s critical national infrastructure.”

The ministry tweeted, “The waves of strikes have largely consisted of air and maritime launched cruise missiles but have almost certainly also included Iranian-provided unmanned aerial vehicles (UAVs) being launched from Russia’s Krasnodar Region.”

Ukraine has said that restoring its pre-2014 border with Russia is its goal in defending against Russia’s nearly 10-month war, including retaking the Crimean Peninsula that Moscow annexed in 2014.

Markarova acknowledged that “taking everything back is difficult,” but added, “There is no other option.”

In this photo taken from handout video released by the Russian Defense Ministry's Press Service Dec. 18, 2022, Russian Defense Minister Sergei Shoigu, right, speaks to officers aboard a military helicopter at an undisclosed location in Ukraine.

In this photo taken from handout video released by the Russian Defense Ministry’s Press Service Dec. 18, 2022, Russian Defense Minister Sergei Shoigu, right, speaks to officers aboard a military helicopter at an undisclosed location in Ukraine.

Russia last week announced the formation of creative brigades to boost the morale of troops on the front line, with plans to send opera singers, actors and circus performers. In a new intelligence update Sunday, however, the British defense ministry said that while “fragile morale almost certainly continues to be a significant vulnerability across much of the Russian force,” the soldiers’ concerns lie elsewhere.

The ministry said, “Soldiers’ concerns primarily focus on very high casualty rates, poor leadership, pay problems, lack of equipment and ammunition, and lack of clarity about the war’s objectives.”

“The creative brigades’ efforts are unlikely to substantively alleviate these concerns,” the British report concluded.

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