Russia claimed to have overrun a key rail hub while its troops fought Ukrainian defenders in the streets of another city in eastern Ukraine.

The Russian Defense Ministry said the railroad center Lyman had been "completely liberated" by a joint force of Russian soldiers and Kremlin-backed separatists.

Meanwhile, nearly 40 miles (60 kilometers) to the east, Russian troops on Saturday sought to encircle Ukrainian defenders in the manufacturing center of Sievierodonetsk, where the fighting cut power and cellphone service and terrorized the civilians who hadn't fled.

Having failed to capture the Ukrainian capital Kyiv early in the 3-month-old war, the Russians set out to seize parts of the eastern industrial region Donbas not already controlled by pro-Moscow separatists. They made grinding progress in Donetsk and Luhansk, the two provinces that make up the Donbas.

Control of Lyman would give Russia's military another foothold in the region. It has bridges for troops and equipment to cross the Siverskiy Donets river, which has so far impeded the Russian advance into the Donbas.

Ukrainian officials have sent mixed signals on Lyman. On Friday, Donetsk Gov. Pavlo Kyrylenko said Russian troops controlled most of it and were trying to press their offensive toward Bakhmut, another city in the region. On Saturday, Deputy Defense Minister Hanna Malyar disputed Moscow's claim that Lyman had fallen, saying fighting there was still ongoing.

In his Saturday video address, Ukrainian President Volodymyr Zelenskyy described the situation in the east as "very complicated" and said that the "Russian army is trying to squeeze at least some result'' by focusing its efforts there.

As his offensive pushed ahead, Russian President Vladimir Putin pressured European leaders to stop arming the embattled Ukrainians and blamed Western sanctions for an emerging global food crisis. The Kremlin said Putin pressed his case in an 80-minute phone call Saturday with the leaders of France and Germany.

German Chancellor Olaf Scholz and French President Emmanuel Macron urged an immediate cease-fire and a withdrawal of Russian troops, according to the chancellor's spokesperson, and called on Putin to engage in serious, direct negotiations with Zelenskyy on ending the fighting.

A Kremlin readout of the call said Putin affirmed "the openness of the Russian side to the resumption of dialogue." The three leaders, who had gone weeks without speaking during the spring, agreed to stay in contact, it added.

But Russia's recent progress in eastern Ukraine could further embolden Putin.

"If Russia did succeed in taking over these areas, it would highly likely be seen by the Kremlin as a substantive political achievement and be portrayed to the Russian people as justifying the invasion," the British Ministry of Defense said in a Saturday assessment.

Russia has intensified efforts to capture the cities of Sievierodonetsk and nearby Lysychansk, which are the last major areas under Ukrainian control in Luhansk.

Luhansk Gov. Serhii Haidai reported that Ukrainian fighters repelled an assault on Sievierodonetsk but Russian troops still pushed to encircle them. He later said Russian forces had seized a hotel on the city's outskirts, damaged 14 high-rise buildings and were fighting in the streets with Ukrainian forces.

Sievierodonetsk Mayor Oleksandr Striuk said there was fighting at the city's bus station. A humanitarian center couldn't operate due to the danger, Striuk said, and cellphone service and electricity were knocked out. And residents risked exposure to shelling to get water from a half-dozen wells, he said.

Some supply routes are functioning, and evacuations of the wounded are still possible, Striuk said. He estimated that 1,500 civilians in the city, which had a prewar population of around 100,000, have died from the fighting as well as from a lack of medicine and diseases that couldn't be treated.

Just south of Sievierodonetsk, Associated Press reporters saw older and ill civilians bundled into soft stretchers and slowly carried down apartment building stairs Friday in Bakhmut.

Svetlana Lvova, the manager of two buildings in Bakhmut, tried to persuade reluctant residents to leave but said she and her husband would not evacuate until their son, who was in Sievierodonetsk, returned home.

"I have to know he is alive. That's why I'm staying here," said Lvova, 66.

On Saturday, people who managed to flee Lysychansk described intensified shelling, especially over the past week, that left them unable to leave basement bomb shelters.

Yanna Skakova left the city Friday with her 18-month-old and 4-year-old sons and cried as she sat in a train bound for western Ukraine. Her husband stayed behind to take care of their house and animals.

"It's too dangerous to stay there now," she said, wiping away tears.

Russia's advance raised fears that residents could experience the same horrors seen in the southeastern port city of Mariupol, which endured a three-month siege before it fell last week. Residents who had not yet fled faced the choice of trying to do so now or staying. Mariupol became a symbol of massive destruction and human suffering, as well as of Ukrainian determination to defend the country.

Mariupol's port has reportedly resumed operations after Russian forces finished clearing mines in the Azov Sea. Russian state news agency Tass reported that a vessel bound for Rostov-on-Don in southern Russia entered the port early Saturday.

In the call with Macron and Scholz, the Kremlin said, Putin emphasized that Russia was working to "establish a peaceful life in Mariupol and other liberated cities in the Donbas."

Ukrainian authorities have reported that Kremlin-installed officials in seized cities have started airing Russian news broadcasts, introduced Russian area codes, imported Russian school curriculum and taken other steps to annex the areas.

Russian-held areas of the southern Kherson region have shifted to Moscow time and "will no longer switch to daylight saving time, as is customary in Ukraine," Russia's state news agency RIA Novosti quoted Krill Stremousov, a Russian-installed local official, as saying Saturday.

In his address Saturday, Zelenskyy also accused Russian forces of preventing Kherson residents from leaving, saying they effectively "try to take people hostage" in a "sign of weakness.''

The war has caused global food shortages because Ukraine is a major exporter of grain and other commodities. Moscow and Kyiv have traded accusations over which side bears responsibility for keeping shipments tied up, with Russia saying Ukrainian sea mines prevented safe passage and Ukraine citing a Russian naval blockade.

The press service of the Ukrainian Naval Forces said two Russian vessels "capable of carrying up to 16 missiles" were ready for action in the Black Sea, adding that only shipping routes established through multilateral treaties may be considered safe.

Ukrainian officials have pleaded with Western nations for more sophisticated and powerful weapons. The U.S. Defense Department would not confirm a Friday CNN report saying the Biden administration was preparing to send long-range rocket systems.

Russia's ambassador to the United States, Anatoliy Antonov, said Saturday that such a move would be "unacceptable" and admonished the White House to "abandon statements about the military victory of Ukraine."

Moscow is also trying to rattle Sweden and Finland's determination to join NATO. Russia's Defense Ministry said its navy successfully launched a new hypersonic missile from the Barents Sea that struck its target about 600 miles (1,000 kilometers) away.

If confirmed, the launch could spell trouble for NATO voyages in the Arctic and North Atlantic. The Zircon, described as the world's fastest non-ballistic missile, can be armed with either a conventional or a nuclear warhead and is said to be impossible to stop with current defense systems.

Last week Russian Defense Minister Sergey Shoigu announced that Russia would form new military units in the country's west in response to Sweden and Finland's bids to join NATO.

From The Associated Press