Explosions and gunfire could be heard Saturday in Ukraine’s capital, Kyiv, as Russian and Ukrainian forces battled for control of the city.

Ukrainian officials are urging the country’s citizens to help defend Kyiv against the Russian forces. An army base in the capital was attacked, but Ukraine’s military said that attack was repelled.

Ukrainian President Volodymyr Zelenskyy had predicted the attacks on Kyiv would become more intense Saturday.

“Kyiv requires special attention,” he said Saturday. “We cannot lose the capital.”

Russian forces advancing on Kyiv and other key cities as part of a plan to "decapitate" Ukraine's government appear to have lost some momentum, U.S. and Western officials said Friday, as they and Moscow ramped up information operations to keep up with fighting on the ground.

Explosions and gunfire Friday continued to rock areas near Kharkiv in the north and Kherson in the south, as Russian forces continued a slow march farther into Ukraine.

A senior U.S. defense official, briefing reporters on the condition of anonymity in order to discuss intelligence, said the Russian forces had unleashed a barrage of more than 200 ballistic and cruise missiles since the invasion began, most of them targeting the Ukrainian military.

But the official said intelligence indicated the operation is not going as smoothly as Russian commanders might have hoped.

“The Russians have lost a little bit of their momentum,” the official said. “They are not advancing as far or as fast as we believe they expected they would.”

The Russian advance on Kyiv, in particular, seems to have gotten bogged down.

“They’re meeting more resistance than they expected,” the U.S. official said, adding that Russian forces had yet to establish air superiority despite a numerical advantage and efforts to eliminate Ukrainian air defenses.

Ukraine’s command and control “is intact,” the official added.

In Kyiv, Zelenskyy sought to rally the nation, rejecting rumors that he had fled the city and insisting he and other government officials “are all here, defending our independence, our state.”

Russian claims

Russian officials countered Friday that their forces had made solid progress in what they described as an effort to eliminate a terrorist threat.

In one social media post, Russian Major General Igor Konashenkov said his country's forces had disabled more than 200 Ukrainian military facilities and dozens of air defense batteries and radar stations, while destroying a handful of Ukrainian combat planes, helicopters and military vehicles.

Russia’s military also said Friday it took control of the strategic Hostomel airport northwest of Kyiv.

Russia’s claim was not immediately confirmed, but Ukrainian authorities reported heavy fighting there.

On the ground in Ukraine

Ukrainian Foreign Minister Dmytro Kuleba, meanwhile, denounced what he called "horrific rocket strikes" on the city, some of which hit civilian areas.

Separately, Kyiv's mayor, former world heavyweight boxing champion Vitali Klitschko, said the city has gone into a defensive phase and warned that Russian saboteurs were on the loose.

Western officials, despite praising Ukrainian forces, cautioned the situation was fluid, and noted that things could change rapidly, especially given that about two-thirds of the 190,000 Russian troops along the Ukrainian border had yet to take part in the fighting.

They also warned of Russian attempts to use disinformation to cloud the situation on the ground and scare Ukraine's forces into submission.

“Our information indicates Russia is creating a disinformation campaign by publicizing false reports about the widespread surrender of Ukrainian troops,” a U.S. official said Friday.

“Our information also indicates that Russia plans to threaten killing the family members of Ukrainian soldiers if they do not surrender,” the official added.

Pentagon press secretary John Kirby praised the Ukrainian forces Friday, even as Russian troops move deeper into the country from the north and the south.

“We see clear indications that Ukrainian armed forces are fighting back and bravely,” he told reporters. “[The Russians] have experienced some setbacks.”

Kirby also said the United States was continuing to find ways to help Ukraine defend itself "both from a lethal and nonlethal perspective.”

NATO response

The Pentagon voiced support for NATO’s decision to activate the NATO Response Force Friday, citing Russia’s aggression.

“It’s not entirely clear if Mr. Putin has designs beyond Ukraine, and it’s because that’s not perfectly clear that we continue to look for ways to bolster our NATO capabilities and to reassure our allies,” Kirby said.

NATO on Friday vowed to continue to support Ukraine’s government and military and warned it had taken unprecedented action to ensure the security of alliance members.

“We are deploying elements of the NATO Response Force on land, at sea, and in the air to further strengthen our posture and to respond quickly to any contingency,” Secretary-General Jens Stoltenberg told reporters in Brussels following a virtual meeting of alliance heads of state.

“There must be no space for miscalculation or misunderstanding,” he said of NATO activating the 40,000-strong force for the first time. “We will do what it takes to protect and defend every ally and every inch of NATO territory.” (VOA)

•PHOTO: A Ukrainian serviceman is seen in the window of a damaged residential building at Koshytsa Street, a suburb of the Ukrainian capital Kyiv, where a military shell allegedly hit, on Feb. 25, 2022.

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