Ukraine has not yet commented on the strike, but the country’s Air Force chief has previously said his forces have destroyed two bridges to weaken enemy logistics.
Military analysts said the bridges were part of critical supply lines for Russian troops defending the area.
Reuters could not independently confirm the damage to the bridges or the battlefield situation in Kursk.
Zelenskyy said on Sunday his troops were unleashing what he described as “maximum counteroffensive actions” aimed at creating a buffer zone and hurting Russia’s military potential.
“Everything that inflicts losses on the Russian army, the Russian state, their military industrial complex and their economy — all this helps us to prevent the widening of the war,” he said.
More than 121,000 people have been relocated from nine border districts in the Kursk region, Russia’s Emergencies Ministry said.
Kremlin presidential aide Yuri Ushakov said Russia was not ready to hold peace talks with Ukraine for now, given its attack on Kursk.
Ukraine has demanded a full withdrawal of Russian troops from its territory before it sits down for any talks.
Ukrainian forces face a tough battle near Pokrovsk, a transport hub for them.
Russian troops were about 10km from the outskirts of the city, said Serhiy Dobriak, head of the local military administration.
He said up to 600 people were leaving daily, and municipal services could be cut off within a week as Russian forces close in.
Regional governor Vadym Filashkin said a curfew in settlements close to Pokrovsk had been tightened and the situation was “very difficult”.
Ukraine’s top general said the army was also “doing everything necessary” to defend the eastern city of Toretsk as Russia tries to target Ukrainian supply lines.
Russia said its forces had captured the nearby town of Zalizne.
The war, which has killed tens of thousands and devastated cities throughout Ukraine, shows no sign of letting up.
Ukraine expects Russia to boost its forces in Ukraine by year’s end to 800,000, up from about 600,000, Ukrainian Deputy Defence Minister Ivan Havryliuk said.
Ukraine has been backed by arms from its allies, but is worried that support may drop as the war grinds on.
The United Kingdom reiterated support for Ukraine on Monday, and Indian Prime Minister Narendra Modi is set to visit Kyiv on August 23.
But German defence stocks fell on Monday after a newspaper said the Finance Ministry would not approve further applications for Ukraine military aid because of budget constraints.
A Finance Ministry spokesperson later said Germany was working intensively with its G7 partners on a plan to make loans available for military support for Ukraine, funded by the proceeds of frozen Russian assets.
In a new sign of tensions over mysterious explosions in 2022 that ruptured the Nord Stream gas pipelines transporting gas under the Baltic Sea, Russia’s RIA news agency said Russia had complained to Germany over its investigation into the incident.
German media reported last week that German prosecutors had identified a Ukrainian diving instructor as a suspect in the Nord Stream sabotage attack and had issued a warrant to arrest him in Poland.
Poland received the German warrant, but the suspect had already left the country because Germany did not include his name in a database of wanted persons, Polish prosecutors said.
Russia believes the German investigation will be closed without identifying those responsible, RIA cited Oleg Tyapkin, the head of the European department at the Russian Foreign Ministry, as saying.
