LONDON — Russian President Vladimir Putin’s continued refusal to accept a ceasefire is “complicating” efforts to reach a peace deal, Ukrainian President Volodymyr Zelenskyy said Saturday, as he prepared to travel to the White House to meet with U.S. President Donald Trump.

Friday’s summit between Trump and Putin in Alaska — to which Ukrainian representatives were not invited — ended with Russia demanding that Ukraine cede the entirety of its contested and fortified eastern Donetsk region in exchange for an end to the fighting, two sources told ABC News.

Putin has repeatedly dodged Ukrainian-U.S. offers of an immediate ceasefire. Before the summit, Trump told reporters, “I want to see a ceasefire rapidly.”

Kyiv has previously rejected ceding any territory to Russia without binding security guarantees that include the U.S. Zelenskyy has also ruled out giving up Donetsk, saying the region could provide a launchpad for future Russian offensives deeper into Ukraine. Kyiv maintains that no peace negotiations can take part until a ceasefire is in effect.

On Saturday, Zelenskyy addressed the ongoing talks in a post to Telegram, saying, “We see that Russia rejects numerous demands for a ceasefire and still has not determined when it will stop the killings. This complicates the situation.”

“If they have no will to implement a simple order to stop the strikes, it may take a lot of effort for Russia to develop the will to implement much more, namely peaceful life with neighbors for decades,” Zelenskyy added. “But we all work together for peace and security. Stopping the killings is a key element of ending the war.”

Zelenskyy will meet Trump at the White House on Monday, with the U.S. president also inviting European leaders to attend.

After the Alaska summit, Trump told Fox News he recommends that Kyiv “make the deal.”

“Look, Russia is a very big power, and they’re not,” Trump said, saying Ukraine had “great soldiers.” The president then praised Putin, calling him a “strong guy” and saying he is “tough as hell.”

Zelenskyy said Saturday he would continue “coordination with partners” ahead of the meeting. “It is important that everyone agrees that a conversation at the leaders’ level is necessary to clarify all the details and determine which steps are needed and will work,” he said.

The Ukrainian president warned earlier on Saturday that Russian operations may expand as peace negotiations continue. “The Russian army may attempt to intensify pressure and strikes against Ukrainian positions in order to create more favorable political conditions for negotiations with global actors,” Zelenskyy posted to Telegram.

Ukraine’s air force said that Russia launched 60 drones and one missile into the country overnight into Sunday, of which 40 drones were shot down or suppressed. Twenty drones impacted across 12 locations, the air force said.

Russia’s Defense Ministry, meanwhile, said its forces shot down at least 52 Ukrainian drones overnight.

ABC News’ Hannah Demissie, Patrick Reevell, Nataliia Popova, Anna Sergeeva, Fidel Pavlenko and Somayeh Malekian contributed to this report.