Another round of talks aimed at stopping the war in Ukraine was scheduled for Tuesday as the fighting appeared stalemated on the ground, with the two sides trading control of a town in the east and a suburb of the capital.

Ukrainian forces retook Irpin, northwest of Kyiv, from Russian troops, who were regrouping to take the area back, President Volodymyr Zelenskyy said late Monday as he sought to rally the country.

"We still have to fight, we have to endure," Zelenskyy said in his nighttime video address to the nation. "We can't express our emotions now. We can't raise expectations, simply so that we don't burn out."

Ahead of the talks in Istanbul, the Ukrainian president said his country is prepared to declare its neutrality, as Moscow has demanded, in comments that might lend momentum to negotiations.

Zelenskyy said over the weekend that compromise might be possible over "the complex issue of Donbas," the hotly contested region in the country's east. It's unclear how that might be reconciled with his stance that "Ukraine's sovereignty and territorial integrity are beyond doubt."

Russia has long demanded that Ukraine drop any hope of joining NATO, which Moscow sees as a threat. Zelenskyy, for his part, has stressed that Ukraine needs security guarantees of its own as part of any deal.

As fighting raged throughout the country, the mayor of Irpin, which has been the scene of some of the heaviest fighting, said the city had been "liberated" from Russian forces.

A senior U.S. defense official said the U.S. believes the Ukrainians have also retaken the town of Trostyanets, south of Sumy, in the east.

The official, who spoke on condition of anonymity to discuss U.S. intelligence assessments, said Russian forces largely remained in defensive positions near the capital, Kyiv, and were making little forward progress elsewhere in the country.

The official said Russia appeared to be de-emphasizing ground operations near Kyiv and concentrating more on the Donbas, the predominantly Russian-speaking region where Moscow-backed rebels have been waging a separatist war for eight years.

Late last week, with its forces bogged down in parts of the country, Russia seemed to scale back its war aims, saying its main goal was gaining control of the Donbas.

The possible face-saving exit strategy for Russian President Vladimir Putin has raised Ukrainian fears the Kremlin aims to split the country, forcing it to surrender a swath of its territory.

In recent days, Ukrainian troops have pushed the Russians back in other sectors.

In the city of Makariv, near a strategic highway west of the capital, Associated Press reporters saw the carcass of a Russian rocket launcher, a burned Russian truck, the body of a Russian soldier and a destroyed Ukrainian tank after fighting there a few days ago.

In the nearby village of Yasnohorodka, the AP witnessed positions abandoned by Ukrainian soldiers who had moved farther west, but no sign of Russian troops.

Russia has destroyed more than 60 religious buildings across the country in just over a month of war, with most of the damage concentrated near Kyiv and in the east, Ukraine's military said in a post Tuesday.

It said the Orthodox church – the country's majority religion – was the most affected but that mosques, synagogues, Protestant churches and religious schools were also destroyed.

A cyberattack knocked Ukraine's national telecommunications provider Ukrtelecom almost completely offline on Monday. The chief of Ukraine's state service for special communication, Yurii Shchyhol, blamed "the enemy" without specifically naming Russia and said most customers were cut off from telephone, internet and mobile service to ensure coverage for Ukraine's military.

Also Monday, an oil depot in western Ukraine's Rivne region was hit by a missile, the governor said, in the second attack on oil facilities in the region near the Polish border.

In other developments:

— Ukraine's prosecutor general said at least 144 children have died in the war so far, most in Kyiv. The tally did not give a number for the besieged eastern city of Mariupol.

— Bloomberg News said it has suspended its operations in Russia and Belarus. Customers in both countries won't be able to access any Bloomberg financial products and trading functions for Russian securities were disabled in line with international sanctions, it said. Bloomberg Philanthropies pledged $40 million, meanwhile, in support for Ukrainians and refugees.

— U.N. Secretary-General Antonio Guterres launched an effort to achieve a humanitarian cease-fire that would allow aid to be brought in and people to move around safely.

— The Group of Seven major economies rejected a Kremlin demand that some countries pay in rubles for Russia's natural gas. That demand appeared designed to support the Russian currency, which is under pressure from Western sanctions.

Earlier talks, both by video and in person, have failed to make progress on ending the more than month-old war that has killed thousands and driven more than 10 million Ukrainians from their homes. That includes almost 4 million who have fled the country.

In the besieged southern port of Mariupol, the mayor said half the pre-war population of more than 400,000 has fled, often under fire, during weeks of shooting and shelling.

Alina Beskrovna, who escaped the city in a convoy of cars and made it to Poland, said desperate people are melting snow for water and cooking on open fires despite the risk of bombardment, "because if you don't, you will have nothing to eat."

"A lot of people are just, I think, starving to death in their apartments right now with no help," she said. "It's a mass murder that's happening at the hands of the Russians."

Putin's ground forces have become bogged down because of stronger-than-expected Ukrainian resistance, combined with what Western officials say are Russian tactical missteps, poor morale, shortages of food, fuel and cold weather gear, and other problems. Moscow has resorted to pummeling Ukrainian cities with artillery and airstrikes.

In Stoyanka village near Kyiv, Ukrainian soldier Serhiy Udod said Russian troops had taken up defensive positions and suffered heavy losses.

The Russians probably "thought it would be like Crimea," which the Kremlin annexed in 2014. "But here it's not like in Crimea. We are not happy to see them. Here they suffer and get killed."

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