UPDATE

KYIV, Ukraine — Russia’s military said today it would “fundamentally” cut back operations near Ukraine’s capital and a northern city, potentially a significant concession by Moscow amid talks aimed at ending the war that began more than a month ago.

Deputy Defense Minister Alexander Fomin said the move was meant “to increase trust” in talks aimed at ending fighting, as negotiators met face-to-face after several rounds of failed negotiations. But Russia’s troops have been bogged down and struggling to make major advances recently.

The talks in Istanbul raised flickering hopes there could be progress toward ending a war that has ground into a bloody campaign of attrition.

Fomin said Moscow had decided to “fundamentally … cut back military activity in the direction of Kyiv and Chernihiv” to “increase mutual trust and create conditions for further negotiations.”

Ukraine’s military said it had noted withdrawals around Kyiv and Chernihiv, though the Pentagon said it could not corroborate the reports,

An adviser to the Ukrainian president said the meeting in Istanbul was focused on securing a cease-fire and guarantees for Ukraine’s security — issues that have been at the heart of previous unsuccessful negotiations.

Ahead of the talks, Ukrainian President Volodymyr Zelenskyy said his country was prepared to declare its neutrality, as Moscow has demanded, and was open to compromise over the contested eastern region of Donbas — comments that might lend momentum to negotiations. But even as the negotiators assembled, Russian forces hit an oil depot in western Ukraine and demolished a government building in the south, with several deaths.

Turkish President Recep Tayyip Erdogan told the two sides that they had a “historic responsibility” to stop the fighting.

“We believe that there will be no losers in a just peace. Prolonging the conflict is not in anyone’s interest,” Erdogan said, as he greeted the two delegations seated on opposite sides of a long table.

Russian President Vladimir Putin’s aim of a quick military victory has been thwarted by stiff Ukrainian resistance. But any hope that raised about prospects for an end to the conflict was accompanied by Western skepticism about the Russian leader’s commitment to seeking peace. British Foreign Secretary Liz Truss said she thought Putin was “not serious about talks.”

In fighting that has devolved into a back-and-forth stalemate, Ukrainian forces retook Irpin, a key suburb northwest of the capital, Kyiv, Zelenskyy said late Monday. But he warned that Russian troops were regrouping to take the area back.

“We still have to fight, we have to endure,” Zelenskyy said in his nighttime video address to the nation. “This is a ruthless war against our nation, against our people, against our children.”

He also lashed out at Western countries, which he has repeatedly accused of not going far enough to punish Moscow with sanctions or support Ukraine. Western hesitancy in providing weapons makes those nations partially responsible for the destruction wrought, he said.

“Fear always makes you an accomplice,” he said.

A missile struck an oil depot in western Ukraine late Monday, the second attack on oil facilities in a region that has been spared the worst of the fighting. This morning, an explosion blasted a hole in a nine-story administration building in Mykolaiv, a southern port city that Russia has unsuccessfully tried to capture.

Seven people died in the missile attack and 22 were wounded, Zelenskyy said in an address to Danish lawmakers.

“It’s terrible. They waited for people to go to work” before striking the building, said regional governor Vitaliy Kim. “I overslept. I’m lucky.”

In other developments:

The head of the United Nations’ nuclear watchdog arrived in Ukraine to try to ensure the safety of the country’s nuclear facilities. Russian forces have taken control of the decommissioned Chernobyl plant, site in 1986 of the world’s worst nuclear accident, and of the active Zaporizhzhia plant, where a building was damaged in fighting.

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 today.

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.

Earlier Russia-Ukraine talks, held in person in Belarus or by video, failed to make progress on ending a more than month-long war that has killed thousands and driven more than 10 million Ukrainians from their homes — including almost 4 million from their country.

Russia has long demanded that Ukraine drop any hope of joining the western NATO alliance, which Moscow sees as a threat. Zelenskyy indicated over the weekend he was open to that, saying Ukraine was ready to declare its neutrality, but he has stressed that the country needs security guarantees of its own as part of any deal. Zelenskyy adviser Mykhailo Podolyak said ending the war was contingent on “international security guarantees for Ukraine.”

Also in the room at the Istanbul talks was Roman Abramovich, a longtime ally of Putin who has been sanctioned by Britain and the EU. Kremlin spokesman Dmitry Peskov said the Chelsea Football Club owner has been serving as an unofficial mediator approved by both countries — but mystery about his role has been deepened by reports that he may have been poisoned during an earlier round of talks.

The investigative news outlet Bellingcat reported Monday that Abramovich and two Ukrainian delegates suffered eye pain and skin irritation consistent with chemical weapons poisoning after attending peace talks on March 3. The British government said the allegations were “very concerning,” but Peskov said the reports ”do not correspond to reality.”

As well as Irpin, Ukrainian forces also seized back control of Trostyanets, south of Sumy in the northeast, after weeks of Russian occupation that has left a landscape devastated by war.

Arriving in the town Monday shortly afterward, The Associated Press saw the bodies of two Russian soldiers lay abandoned in the woods and Russian tanks lay burned and twisted. A red “Z” marked a Russian truck, its windshield fractured, near stacked boxes of ammunition. Ukrainian forces piled atop a tank flashed victory signs. Dazed residents lined up amid charred buildings seeking aid.

It was unclear where the Russian troops went, under what circumstances they fled and whether the town will remain free of them.

Ukraine, meanwhile, said it would try to evacuate civilians from three southern cities today. Deputy Prime Minister Iryna Vereshchuk said humanitarian corridors would run from heavily bombed Mariupol as well as Enerhodar and Melitopol. The latter two cities are under Russian control, but Vereshchuk didn’t say whether Moscow had agreed to the corridors.

Putin’s ground forces have become bogged down because of the 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.

In response, Russia appeared to be concentrating more on Donbas, the predominantly Russian-speaking region where Moscow-backed rebels have been waging a separatist war for eight years, the official said.

In a further indication of that shift, Russian Defense Minister Sergei Shoigu said today that “liberating Donbas” was Moscow’s main military goal.

Shoigu, whose few public appearances this month raised questions about his health and whereabouts, told top military officials that Russia had largely completed the first stage of its operation and was shifting to “the main goal — the liberation of Donbas.”

While that presents a possible face-saving exit strategy for Putin, it has also raised Ukrainian fears the Kremlin aims to split the country, forcing it to surrender a swath of its territory. Still, Zelenskyy’s comments that he was open to compromise on the region indicated a possible path for negotiations.