President Donald Trump has said Russia’s deadly missile attack on the Ukrainian city of Sumy was “a mistake,” calling it a “horrible thing” even as members of his administration went further with condemnation that served as a rare critique of Moscow while the White House is pushing for a ceasefire.

Two ballistic missiles killed at least 35 people and injured more than 100 in Sumy on Sunday morning. The attack was the second in just over a week to inflict heavy civilian casualties in Ukraine, which Ukraine has said shows that Moscow is not truly interested in a truce.

“I think it was terrible. And I was told they made a mistake. But I think it’s a horrible thing,” Trump said about the Sumy attack when he was aboard Air Force One on Sunday.

Russia’s foreign minister, Sergey Lavrov, told the Kommersant newspaper on Monday that Moscow had targeted “a get-together of Ukrainian military chiefs with their Western counterparts” in Sumy. He declined to comment on the civilian deaths.Ukraine’s military did not say whether any service members were killed in the attack, and several videos of the aftermath showed only casualties in civilian clothes. But Ukrainian news media, citing local military officials, reported that Col. Yuriy Yula, a commander in the 27th Brigade, had died in Sumy.

It was not immediately clear what Trump meant when he said he had been “told” Russia “made a mistake” — a formulation that could also be interpreted as an attempt to make excuses for Moscow. Trump has generally avoided criticizing President Vladimir Putin of Russia since taking office in January.

Some top officials in the Trump administration were more explicit. Keith Kellogg, a retired U.S. general and Trump’s special envoy for Ukraine, said that Russian forces had crossed “any line of decency” by targeting civilians in Sumy. Secretary of State Marco Rubio also condemned what he described as a “horrifying Russian missile attack on Sumy.”

“This is a tragic reminder of why President Trump and his Administration are putting so much time and effort into trying to end this war and achieve durable peace,” Rubio wrote on social media.

The condemnations came as the U.S. efforts to broker a ceasefire have failed to yield results. In recent days, White House officials have said that Russia was running out of time to convince the Trump administration that it is serious about striking a peace deal — and not just playing for time.

Ukrainian officials have said that Russia is slow-walking the negotiations because it has no interest in halting the fighting while its army retains the advantage on the battlefield.

In an interview broadcast Sunday but recorded before the attack on Sumy, President Volodymyr Zelenskyy invited Trump to Ukraine to witness the realities of the war firsthand.

“Come, look, and then let’s move with a plan on how to finish the war. You will understand with whom you have a deal. You will understand what Putin did,” Zelenskyy told “60 Minutes” on CBS.

Zelenskyy was speaking with the broadcaster from Kryvyi Rih, his home city, where a Russian missile strike killed 19 people, including nine children, earlier this month.

“We respect your position,” he added, apparently a reference to Trump’s efforts to restore ties with Russia. “But, please, before making any decisions or plans for negotiations, come to see the people, civilians, warriors, hospitals, churches, children destroyed or dead.”

Ukrainian officials said that Russian missiles hit Sumy, just 18 miles from the Russian border, as many people were out on the streets celebrating Palm Sunday, a Christian holiday widely observed in Ukraine. Videos of the aftermath showed scenes of devastation, with bloodied bodies lying motionless in the street and charred cars.

“There was a girl, maybe 14 years old — dead. A young woman — I won’t even describe the injuries, they were horrific. Another middle-aged woman had her jaw torn off,” said Volodymyr Boiko, a 69-year-old resident of Sumy who was in a bus hit by the blast wave. He suffered cuts to his face from flying shards.

The strike came just two days after Trump’s special envoy, Steve Witkoff, met with Putin in St. Petersburg, Russia, to discuss a potential ceasefire.

The timing led some in Ukraine to suggest that Trump’s attempts to reengage with Russia were only emboldening the Kremlin to continue its aggression. Memes proliferated on Ukrainian social media showing Witkoff shaking Putin’s hand with the carnage in Sumy as a backdrop.

In his nightly address on Sunday, Zelenskyy noted that it had been two months since Russia refused to agree to the unconditional ceasefire that Ukraine had accepted with U.S. urging.

“They are not afraid. That’s why they keep launching ballistic missiles,” he said.