Russia unleashed another large-scale aerial assault on Ukraine early Tuesday, killing at least 21 people in Kyiv and Dnipro and prompting renewed appeals from President Volodymyr Zelensky for additional support from the United States and its allies as the war enters its fourth year.

Ukrainian authorities said Moscow launched more than 600 drones alongside dozens of missiles in one of the latest mass bombardments targeting civilian infrastructure across the country. The attacks struck multiple locations, damaging hospitals, residential buildings and critical facilities as air raid sirens sounded across major cities.

The deadliest impacts were reported in Kyiv and Dnipro. Officials said six people were killed in the Ukrainian capital, while another 15 died in Dnipro, including two children. Emergency crews continued search and rescue operations throughout the day as authorities assessed the full scale of the damage.

CNN reported that approximately 41,000 people sought shelter in Kyiv's underground metro stations during the attack, the highest number recorded in years. The scenes highlighted the growing strain on civilians as Russia intensifies its long-range strike campaign against urban centers.

According to Ukrainian officials, at least five medical facilities suffered damage during the barrage. Images released by local authorities showed shattered windows, damaged structures and debris scattered across residential neighborhoods.

The attack comes as Russia has increasingly relied on large-scale drone and missile operations to pressure Ukraine's defenses. Military analysts say both sides have adapted to a battlefield increasingly defined by unmanned systems, long-range strikes and attritional warfare along heavily fortified front lines.

The New York Times recently reported that both Russia and Ukraine have significantly expanded domestic drone production, turning relatively inexpensive unmanned aircraft into a central component of military strategy. Drones are now routinely used for reconnaissance, precision attacks and strikes deep behind enemy lines.

While Russia continues its aerial campaign, questions have emerged about the financial burden of sustaining the war. Bloomberg reported that senior Russian economic officials warned President Vladimir Putin that military spending at current levels may be difficult to maintain. According to the report, officials from Russia's Finance Ministry and central bank cautioned that continued expenditures risk significantly widening budget deficits.

At the same time, Ukrainian military commanders argue that Russia's battlefield momentum may be slowing despite its continued missile and drone attacks. Brigadier General Andriy Biletsky told Reuters that Russian forces have suffered substantial losses and are no longer capable of achieving major operational breakthroughs.

Biletsky said Ukraine's military continues adapting through expanded drone operations and precision strikes against Russian targets. Looking ahead, he argued that the coming months could prove decisive for both sides.

"I believe the next six to nine months are a turning point," Biletsky told Reuters.

He added that Ukraine must continue improving its military position before any future negotiations. "We need to define those directions where we can improve our positions, take some strategic points, and then speak with the Russians from a position of strength - not weakness - about a truly stable truce," Biletsky said.