KYIV, UKRAINE, MARCH 30

Russian forces pounded areas around Kyiv and another Ukrainian city overnight, local officials said Wednesday, just hours after Moscow pledged to scale back military operations in those places. The shelling further tempered optimism about possible progress in talks aimed at ending the punishing war.

Russia did not spell out what exactly a reduction in activity would look like, and while the promise initially raised hopes that a path toward ending the bloody war of attrition was at hand, Ukraine's president and others cautioned that the commitments could merely be bluster.

Moscow, meanwhile, reacted coolly Wednesday to Kyiv's proposed framework for a peace deal, with Kremlin spokesman Dmitry Peskov saying it was a "positive factor" that Ukraine has submitted its written proposals but adding that he saw no breakthrough.

The British Defense Ministry said heavy losses have forced some Russian units to return to Belarus and Russia to regroup but that Moscow would likely compensate for any reduction in ground maneuvers by using mass artillery and missile barrages. And the Russian military reported a new series of missile strikes on Ukrainian arsenals and fuel depots over the past 24 hours.

As the war unleashed five weeks ago by Moscow ground on, so, too, did the fallout beyond Ukraine's borders. The United Nations said the number of refugees fleeing the country has now surpassed a staggering 4 million, while European industrial powerhouse Germany issued a warning over its natural gas supplies amid concerns that Russia could cut off deliveries unless it is paid in rubles.

Ukrainian President Volodymyr Zelenskyy reacted with skepticism to Russia's announcement at talks in Istanbul on Tuesday that it would reduce military activity near the capital and the northern city of Chernihiv.

"We can call those signals that we hear at the negotiations positive," he said in his nightly video address to the Ukrainian people. "But those signals don't silence the explosions of Russian shells."

That skepticism appeared well placed by Wednesday morning.

"The so-called reduction of activity in the Chernihiv region, was demonstrated by the enemy strikes including air strikes on Nizhyn, and all night long they were shelling Chernihiv," said the regional governor, Viacheslav Chaus. "Civilian infrastructure facilities, libraries, shopping centers, many houses were destroyed in Chernihiv."

Oleksandr Pavliuk, the head of the Kyiv region military administration, said Wednesday that Russian shells targeted residential areas and civilian infrastructure in the Bucha, Brovary and Vyshhorod regions around the capital.

They weren't the only attacks by Moscow.

Russian Defense Ministry spokesman Maj. Gen. Igor Konashenkov said Wednesday that the military targeted fuel depots in two towns in central Ukraine with air-launched long-range cruise missiles. Russian forces also hit a Ukrainian special forces headquarters in the southern Mykolaiv region, he said, and two ammunition depots in the eastern Donetsk region.

Donetsk is in the eastern industrial heartland of Donbas, where the Russian military says it has shifted its focus. Top Russian military officials have said twice in recent days that their main goal now is the "liberation" of Donbas, where Moscow-backed rebels have been battling Ukrainian forces since 2014.

Some analysts have suggested that the Kremlin's apparent lowering of its aims and the pledge to reduce activity around Kyiv and Chernihiv may merely reflect the reality on the ground: Its ground troops have become bogged down and taken heavy losses in their bid to seize the capital and other cities.

Still, the outlines of a possible deal to end the war came into view at the latest round of talks Tuesday in Istanbul.

Ukraine's delegation offered a detailed framework for a peace deal under which a neutral Ukraine's security would be guaranteed by a group of third countries, including the US, Britain, France, Turkey, China and Poland. Among other things, the Kremlin has demanded all along that Ukraine drop any hope of joining NATO.

Russian delegation head Vladimir Medinsky said negotiators would take them to Russian President Vladimir Putin and then Moscow would provide a response, but he did not say when.

Russian Deputy Defense Minister Alexander Fomin said Moscow would in the meantime "fundamentally ... cut back military activity in the direction of Kyiv and Chernihiv" to "increase mutual trust and create conditions for further negotiations."

The talks had been expected to resume on Wednesday, but with what Turkish Foreign Minister Mevlut Cavusoglu called "meaningful" progress made, the two sides decided to return home for consultations.

Despite the apparent signs of progress, Zelenskyy warned the world and his own people not to get ahead of themselves.

"Ukrainians are not naïve people," he said. "Ukrainians have already learned during the 34 days of the invasion and during the past eight years of war in the Donbas that you can trust only concrete results."

Western countries also expressed doubts about Russia's intentions.

"We judge the Russian military machine by its actions, not just its words," British Deputy Prime Minister Dominic Raab told Sky News on Wednesday. "There's obviously some skepticism that it will regroup to attack again rather than seriously engaging in diplomacy."

He added that "of course the door to diplomacy will always be left ajar, but I don't think you can trust what is coming out of the mouth of Putin's war machine."

An assessment from Britain's Ministry of Defense said that Russia's focus on the Donbas region "is likely a tacit admission that it is struggling to sustain more than one significant axis of advance."

"Russian units suffering heavy losses have been forced to return to Belarus and Russia to reorganize and resupply," the ministry said in a statement Wednesday. "Such activity is placing further pressure on Russia's already strained logistics and demonstrates the difficulties Russia is having reorganizing its units in forward areas within Ukraine."

Pentagon spokesman John Kirby said the US has detected small numbers of Russian ground forces moving away from the Kyiv area, but it appeared to be a repositioning of forces, "not a real withdrawal."

In response to Moscow's pledge, US President Joe Biden and his secretary of state, Antony Blinken, said they would wait to see what Russia's actions are.

Blinken added that Russian indications of a pullback could be an attempt to "deceive people and deflect attention."

It wouldn't be the first time. In the tense buildup to the invasion, the Russian military announced some units were loading equipment onto rail cars and preparing to return to their home bases after completing exercises. At the time, Putin signaled interest in diplomacy. But 10 days later, Russia launched its invasion.

Western officials say Moscow is now reinforcing troops in the Donbas in a bid to encircle Ukraine's forces there. And Russia's deadly siege in the south continues, with civilians trapped in the ruins of Mariupol and other devastated cities. The latest satellite imagery from Maxar Technologies showed hundreds of people waiting outside a grocery store in besieged Mariupol amid reports of food and water shortages.

Even as negotiators gathered Tuesday, Putin's forces blasted a gaping hole in a nine-story government administration building in a strike on the southern port city of Mykolaiv, killing at least 14 people, emergency authorities said.

"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."