A large-scale Russian drone attack against Ukraine took place Wednesday, killing six people ​and ‌wounding dozens across the country, Ukrainian President Volodymyr ‌Zelenskyy said.

The attack represents one of the longest and largest ​attacks in Russia's war in Ukraine, Zelenskyy said.

"Since midnight, ‌at ​least 800 Russian drones have already been launched, ​and the attack is ongoing, with ⁠additional ​drones entering our ​country's airspace," he wrote on ‌X.

Zelenskyy said the daytime attack was "deliberately targeting our railway infrastructure and civilian sites in our cities."

On Telegram, Zelenskyy said an attack on Kyiv, the western city of Lviv, and the port of Odesa, began midmorning and lasted for hours. 

The strikes also targeted Ukraine's residential and railway infrastructure in the central Dnipro and northeastern Kharkiv regions, and energy facilities in the central Poltava region, Zelenskyy said.

The Polish army said it had scrambled fighter jets as a preventative measure due to the Russian air strikes in far western Ukraine. 

Slovakia briefly closed its border Wednesday with Ukraine for security reasons as a nearby Ukrainian city came under Russian attack. 

Attacks come as Trump and Xi meet

Zelenskyy condemned the attacks, saying it "cannot be called a coincidence" that the attack has taken place at the same time that US President Donald Trump arrived in China for a high-profile state visit.

"In this difficult geopolitical moment, Russia is clearly trying to disrupt the overall political atmosphere and draw attention to its evil — seeking to do so at the expense of Ukrainian lives and Ukrainian infrastructure," he wrote on X.

"It is important to support Ukraine and not remain silent about Russia’s war. Every time the war disappears from the top of the news, it encourages Russia to become even more savage,” Zelenskyy said, a reference to the world's attention being caught by the Iran war.

On Tuesday, prior to the attack, Trump said he believes Moscow and Kyiv will soon reach a deal to end fighting. "The end of the war in Ukraine I really think is getting very close," Trump told reporters as he left for Beijing.

Russia's use of drones 'evolving'

Serhiy Beskrestnov, an adviser ⁠to ​Ukraine's defense minister, said the attack involved large numbers of drones moving along between 5 kilometers and 10 kilometers (between 3 and 6 miles) from ​the Belarus border with the aim of overwhelming ‌Ukraine's air defenses and breaking through to the western regions.

Beskrestnov noted that the strike highlighted the evolving use of drones ​by Moscow, with tactics changing from attack to attack.

Russia has denied intentionally attacking civilians, despite thousands of them dying in its attacks against Ukraine. Moscow has said strikes on civilian infrastructure are legitimate if they weaken Ukraine's ability to fight.

On Wednesday, Zelenskyy said Ukraine will send experts to Latvia to assist in building a "multi-layered air defense system against different types of threats."

It comes after two supposedly stray Ukrainian drones hit ​infrastructure Latvia ‌after crossing from Russia. Ukraine said the mishap was due to "Russian electronic warfare."

Latvian Prime Minister Evika Silina said anti-drone systems had not been deployed quickly enough.

Edited by: Wesley Dockery