Ukrainians Try to Push Back Russian Forces Pummeling Their Cities

Ukrainian forces pressed to thwart the Russian invasion, mounting counteroffensives on multiple fronts and retaking a town outside of Kyiv on Tuesday, while the more heavily armed Russians, unable so far to gain a decisive upper hand, tried to pound Ukraine’s cities and people into submission.

As the fighting seesawed around Kyiv, Ukrainian military officials said their forces had prevailed in Makariv, a key crossroads on the western approaches to the city, while in the south of the country they sought to reclaim the Kherson region. The southern port of Mariupol still endured a brutal siege, however, with the government saying that some 100,000 civilians remained trapped in that ruined city with little food, water, power or heat.

“This war will not end easily or rapidly,” Jake Sullivan, the U.S. national security adviser, told reporters on the eve of President Biden’s departure for a NATO summit in Europe.

Mr. Biden is set to impose sanctions this week on hundreds of members of the State Duma, Russia’s lower house of Parliament, according to a person familiar with the planned announcement.

In Russia, President Vladimir V. Putin’s government, which had apparently expected a lightning conquest, responded to its setbacks in Ukraine and its plummeting reputation in the West by expanding its recent draconian crackdown on dissent, making it a criminal offense to discredit the activities of all state agencies working abroad, like embassies. A Russian court sentenced the already imprisoned opposition leader Aleksei A. Navalny, who opposes Russia’s war on Ukraine, to nine more years in prison on fraud charges.

A Pentagon assessment concluded that Russia’s “combat power” in Ukraine had for the first time dipped below 90 percent of its original force — the more than 150,000 troops massed in western Russia and Belarus before the Feb. 24 invasion. That reflected steady losses suffered by the Russian military, to an extent that U.S. officials say can leave units unable to carry out combat duties.

Russian forces were “struggling on many fronts,” including routine supply lines and logistics, according to a senior Defense Department official, who was not authorized to discuss details of Russia’s actions in Ukraine on the record. The Pentagon had even seen indications that some Russian troops had been evacuated because of frostbite, the official said.

The official declined to address Russian casualty numbers, though the Pentagon estimated last week that at least 7,000 Russians had been killed.

New satellite imagery analyzed by The New York Times showed that Russia had removed all of its aircraft from the airport of the southern city of Kherson, the largest city that the Russian forces have captured so far. Ukrainian forces have claimed to hit the airport twice, destroying an undetermined number of helicopters. The removal is a telltale sign that the Russians are struggling as they seek to control the region, experts said.

The removal of the equipment, visible by comparing pictures taken by the space imaging company Planet Labs over six days, comes as the Ukrainian army is pressing to reclaim lost territory in the Kherson region.

Control over Kherson, taken by Russia on March 2, is essential in any effort to control the south of Ukraine. But Russia has failed to dominate the region as a whole.

Dmitri S. Peskov, the spokesman for Mr. Putin, repeatedly refused to rule out the possibility of Russia using nuclear weapons during a television interview on Tuesday. When asked under what conditions Mr. Putin would use such weapons, Mr. Peskov told CNN, “if it is an existential threat for our country, then it can be.” While he did not define “existential threat,” in the past Russian officials have suggested that it meant an attack on Russia itself, but the invasion of Ukraine has thrown previous policy into question.

It is hard to assess the current landscape of the war there, with a senior U.S. defense official only characterizing the fighting as “a very dynamic, active battlefront.”

The Pentagon has seen no indication that Russian forces are moving toward the use of chemical or biological weapons, the official said.

On Monday, Mr. Biden stressed the possibility that Mr. Putin might turn to such weapons, which are banned by international treaty. “His back is against the wall,” Mr. Biden said at a meeting of U.S. business leaders.

Mr. Biden is due to attend a summit of NATO leaders in Brussels on Thursday that among other issues will discuss a potential response to any such weapons. The United States will also announce new sanctions on Russia in conjunction with its NATO allies, said Mr. Sullivan.

“For the past few months, the West has been united,” he said. “The president is traveling to Europe to ensure we stay united, to cement our collective resolve, to send a powerful message that we are prepared and committed to this for as long as it takes.”

In Ukraine, the Defense Ministry announced that its troops had raised the blue and gold Ukrainian flag over Makariv, about 40 miles west of Kyiv, where control has repeatedly changed hands. The town abuts the key highway that leads from the capital to western Ukraine and Lviv, so keeping it out of Russian hands is important in the effort to prevent Kyiv from being encircled.

The Russians had not been able to advance beyond nine miles northwest of Kyiv or 18 miles from the city’s east — essentially where they were last week, the senior Pentagon official said.

The Ukrainian determination to push back extended to the air force and air defense units, which have managed to continue fighting despite being vastly outnumbered and outgunned by the Russians.

President Volodymyr Zelensky of Ukraine said that the besieged city of Mariupol, a port on the Sea of Azov, was being “reduced to ashes.” Some 100,000 civilians, or 22 percent of the original population, remain stuck there, the government said. The Pentagon official said that Russian naval ships had joined land forces in bombarding the city. Russia’s Black Sea fleet is headquartered on the nearby Crimean Peninsula, and a dozen ships are plying the waters off Ukraine, according to the Pentagon.

Mr. Zelensky, continuing to address parliaments around the world via video link, warned Italy’s Parliament that famine would strike parts of the world if farmers in Ukraine, a major wheat producer, were unable to work. “Famine was approaching for several countries” that depended on Ukrainian corn, oil and wheat, he said, including North African states just across the Mediterranean Sea from Italy.

In response, Prime Minister Mario Draghi of Italy said that his country wanted Ukraine to join the European Union, and praised the “heroic” resistance of the Ukrainians against the “ferociousness” of Mr. Putin.

Mr. Draghi said that Italy had frozen more than 800 million euros (almost $900 million) worth of assets from Russian oligarchs and was working to overcome its dependency on Russian energy supplies as fast as possible.

At the United Nations, António Guterres, the secretary general, said that 10 million Ukrainians had been displaced from their homes, or just under one quarter of the population.

Mr. Guterres called the war in Ukraine unwinnable. Ukrainians were “enduring a living hell — and the reverberations are being felt worldwide with skyrocketing food, energy and fertilizer prices threatening to spiral into a global hunger crisis,” he said. Guterres repeated his plea for Russia to stop the war, calling for serious negotiations.

The Russian Parliament, the Duma, which reliably does the Kremlin’s bidding, amended an already draconian censorship law to make “discrediting” the activities abroad of all government bodies — not just the military — a potentially criminal offense. The law bars terms like “war” or “invasion” to describe Russia’s military operations in Ukraine, punishing anyone spreading “false information” about the invasion with up to 15 years in prison. Russia has taken other moves to quell information, prompting independent news outlets to shut down or move operations out of the country for fear of punishment, and it has blocked access to Facebook and Instagram, both heavily used by government officials and businesses.

The conviction and sentencing of Mr. Navalny was widely seen as a way to keep him behind bars and further restrict his ability to address the outside world, as the Kremlin tries to tightly control the narrative about the war at home and stamp out glimmers of defiance. Mr. Navalny has urged Russians to protest the invasion, via letters from jail that his lawyers post on social media.

Zhanna Agalakova, an accomplished Russian foreign correspondent who resigned earlier this month from Channel One, among the most popular networks in a country where the state controls virtually all broadcasts, announced that she had quit to protest Russia’s invasion of Ukraine. “I’m doing this for Russians,” she said in a series of Twitter posts via Reporters Without Borders. “Our news doesn’t show the reality.”

Reporting was contributed by John Ismay in Washington; Marc Santora in Krakow, Poland; Andrew E. Kramer in Kyiv, Ukraine; Dan Bilefsky in Montreal; Anton Troianovski in Istanbul; Valeriya Safronova; Gaia Pianigiani in Rome; Christiaan Triebert in Paje, Tanzania; and Christoph Koettl and Farnaz Fassihi in New York.