Russia launched one of its biggest aerial attacks this year at Ukraine, firing 574 drones and 40 missiles overnight, the Ukrainian Air Force said Thursday. The attack mostly targeted western regions of the country, the military branch said.

The strikes killed at least one person in Lviv, and injured 15 others, according to officials.

Ukraine's Foreign Minister Andrii Sybiha said Russia struck a "major American electronics manufacturer" in western Ukraine. 

Western parts of Ukraine are far from the battlefield's front line in the east and south of the country. Much of the military aid provided by Ukraine's Western allies is believed to be transported and stored there.

It was Russia's third largest aerial attack this year in terms of the number of drones fired and the eighth-largest in terms of missiles, according to official figures.

The strikes occurred during a renewed effort by Western countries to reach a peace settlement in the three-year war following Russia's invasion of its neighbour.

Ukrainian President Volodymyr Zelenskyy condemned the attack, saying it was carried out "as if nothing were changing at all."

Moscow has shown no signs of pursuing meaningful negotiations to end the war and urged the international community to respond with stronger pressure, including tougher sanctions and tariffs, he said.  

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Russia "wasted several cruise missiles against an American business," Zelenskyy said, noting it was a company producing domestic utilities, such as coffee machines. "And that too became a target for Russia. Very telling."

Mukachevo Mayor Andriy Baloha said the damaged enterprise belonged to Flex Ltd., which is a NASDAQ-listed company. The corporate headquarters of the company — a global technology, supply chain and advanced manufacturing solutions partner — is in Austin, Texas, and its registered office is in Singapore.

Flex, which grew from a family firm founded in Silicon Valley in 1969, employed thousands of the area's residents, Baloha said.

At the moment of impact, 600 night-shift workers were on the premises, and six of them were injured, Andy Hunder, president of the American Chamber of Commerce in Ukraine, told the Associated Press.

Russia's Defence Ministry said the strikes targeted "enterprises of the Ukrainian military-industrial complex." It claimed the attack hit drone factories, storage depots and missile launch sites, as well as areas where Ukrainian troops were gathered. Russia has repeatedly denied targeting civilian areas of Ukraine.

Ukraine, meanwhile, has kept up its attacks with domestically produced long-range drones on infrastructure inside Russia that supports Moscow's war effort. Among other targets, it has hit oil refineries, and Russian wholesale gasoline prices have reached record highs in recent days.

Ukrainian drones struck Russia's Novoshakhtinsk oil refinery in an overnight attack that caused multiple explosions, the Ukrainian general staff said on Thursday. Kyiv also attacked a fuel base in Russia's Voronezh region, and a drone warehouse and logistics hub in Russia-occupied Donetsk, it said.

Earlier, Zelenskyy said Ukraine will hold intensive meetings to gain clarity over what kind of support it can expect from allies. A coalition of more than 30 countries have in principle pledged to contribute to security guarantees but talks came to a standstill when the U.S. remained ambivalent about its role. 

Zelenskyy reiterated that Ukraine is ready to hold direct talks with Putin. The two leaders have not met in person since late 2019, at a gathering in which several world leaders attended.

"And what if the Russians are not ready? The Europeans raised the issue. If the Russians are not ready, then we would like to see a strong reaction from the United States," he said.

Ukraine previously has expressed hope that the U.S. will punish Russia with more sanctions if it does not demonstrate a serious willingness to end the war.

Speaking to the media Wednesday, Russian Foreign Minister Sergei Lavrov said that working on security arrangements in Ukraine without Moscow's involvement would not work.