Zelenskiy said he would speak with US President Donald Trump later on Wednesday and expected to hear more about the American leader's phone call with Putin about a ceasefire and to discuss the next steps to be taken.
"Even last night, after Putin's conversation with ... Trump, when Putin said that he was allegedly giving orders to stop strikes on Ukrainian energy, there were 150 drones launched overnight, including on energy facilities," Zelenskiy said at a news conference in Helsinki with Finnish President Alexander Stubb.
The strikes, which hit civilian areas and damaged a hospital, followed Putin's refusal to back a full 30-day ceasefire during discussions with Trump.
The White House described the call between Trump and Putin as the first step in a "movement to peace" that Washington hopes will include a maritime ceasefire in the Black Sea and eventually a full and lasting end to the fighting.
But there was no indication that Putin backed away from his conditions for a prospective peace deal, which are fiercely opposed by Kyiv.
Zelenskiy said that one of the most difficult issues in future negotiations would be the issue of territorial concessions.
"For us, the red line is the recognition of the Ukrainian temporarily occupied territories as Russian," he said. "We will not go for it."
Shortly after the lengthy phone call between Trump and Putin on Tuesday, air raid sirens sounded in Kyiv, followed by explosions as residents took shelter.
Despite efforts to repel the attack, several strikes hit civilian infrastructure, including a direct drone strike on a hospital in Sumy and attacks on cities in Donetsk region.
Russian drones were also reported over Kyiv, Zhytomyr, Sumy, Chernihiv, Poltava, Kharkiv, Kirovohrad, Dnipropetrovsk, and Cherkasy regions.
The Russian defence ministry reported Wednesday that its air defenses intercepted 57 Ukrainian drones over the Azov Sea and several Russian regions - the border provinces of Kursk and Bryansk and the nearby regions of Oryol and Tula.
Separately, authorities in the Krasnodar region bordering the Crimean Peninsula, which was annexed by Russia in 2014, reported that a drone attack there started a fire at an oil depot.
