U.S. President Donald Trump has labeled Russian President Vladimir Putin “crazy” in response to the most extensive drone and missile attack Russia has launched on Ukraine since the start of the full-scale war in 2022.

In a Truth Social post, Trump wrote, “Something has happened to him. He has gone absolutely crazy. He is needlessly killing a lot of people.” The comment came after a massive wave of Russian strikes that saw 355 drones and nine cruise missiles launched at Ukraine between Sunday night and Monday morning, according to Ukraine’s air force.

Ukrainian officials confirmed that at least 12 people were killed and dozens more injured in the overnight assault. Air raid sirens sounded across multiple regions, and emergency crews worked through the wreckage of homes destroyed in the Kyiv region.

Ukrainian President Volodymyr Zelensky condemned the attack, stating, “Only a sense of total impunity allows Russia to carry out such strikes and continue increasing their scale.” Kyiv also criticized Washington's perceived silence on recent escalations and called for tougher sanctions on Moscow.

In response to the U.S. president’s remarks, Kremlin spokesperson Dmitry Peskov acknowledged the "emotional overload" involved but said Putin was making decisions necessary for Russia’s security. He also claimed the aerial assault was a response to Ukrainian strikes on Russian "social infrastructure."

Despite his sharp words for Putin, Trump also took aim at Zelensky, accusing the Ukrainian leader of unhelpful rhetoric. “He is doing his country no favours by talking the way he does,” Trump wrote. “Everything out of his mouth causes problems, I don’t like it, and it better stop.”

Trump indicated he was considering ramping up sanctions against Russia, stating, “Absolutely,” when asked about the possibility. However, despite repeated threats, his administration has not yet enacted any new restrictions on Moscow.

The backdrop to these developments includes recent diplomatic engagement. Trump and Putin reportedly held a two-hour phone conversation last week discussing a U.S.-led ceasefire proposal. Trump claimed the talk went “very well” and expressed optimism that peace negotiations would begin immediately.

While Ukraine has agreed to a 30-day ceasefire, Russia has not confirmed any formal agreement, instead proposing to work on a “memorandum” for a potential future peace—an approach Ukraine and its European allies view as a stalling tactic.

The latest round of direct talks between Russia and Ukraine took place on May 16 in Istanbul, but yielded little concrete progress beyond a prisoner swap. Russia still occupies around 20% of Ukrainian territory, including Crimea, which it annexed in 2014.

Despite hopes for peace, the scale and intensity of the latest attacks underscore the war's ongoing brutality and the fragile state of diplomatic efforts.