KYIV, Ukraine — Russia launched its biggest drone attack against Ukraine overnight Sunday, a Ukrainian official said Monday, part of an escalating bombing campaign that has further dashed hopes for a breakthrough in efforts to end the 3-year-old war.

On the third straight night of significant aerial bombardments, U.S. President Donald Trump lashed out at Russian leader Vladimir Putin, saying he had gone “crazy” by stepping up attacks on Ukraine.

Trump also expressed frustration with Ukrainian President Volodymyr Zelenskyy’s comments in general.

The expansion of Russia’s air campaign appeared to be another setback to U.S.-led peace efforts, as Putin looks determined to capture more Ukrainian territory and inflict more damage. It comes after Kyiv accepted an unconditional 30-day ceasefire in March that was proposed by the U.S. but that Moscow effectively rejected.

This month alone, Russia has broken its record for aerial bombardments of Ukraine three times.

Russia is also still pushing along the 620-mile front line, where it has made slow and costly progress, and is assembling its forces for a summer offensive, analysts say.

“Only a sense of complete impunity can allow Russia to carry out such attacks and continually escalate their scale,” Zelenskyy wrote on Telegram on Monday. “There is no significant military logic to this, but there is considerable political meaning.”

The Russian bombardment Sunday night included 355 drones, Yuriy Ihnat, head of the Ukrainian air force’s communications department, told The Associated Press, calling it the biggest of the war.

The previous night, Russia fired 298 drones and 69 missiles in what Ukrainian officials said was the largest combined aerial assault of the conflict. From Friday to Sunday, Russia launched around 900 drones at Ukraine, officials said.

Russia’s Defense Ministry said Monday that its forces shot down 103 Ukrainian drones overnight that were flying over southern and western Russia, including near Moscow. Russia’s Federal Air Transport Agency said 32 flights scheduled to land at three Moscow airports on Sunday and Monday had to divert amid Ukrainian drone attacks.

The numbers from Ukraine and Russia could not be independently verified.

Soon after Russia’s Feb. 24, 2022, invasion, the conflict became a testing ground for sophisticated drone warfare. Drones are generally cheaper to produce than missiles.

Russia has received Iranian-made Shahed drones since 2022 and is believed to be manufacturing its own version.

Also Monday, German Chancellor Friedrich Merz said there are “no longer any range restrictions for weapons that have been delivered to Ukraine — neither by the British, nor by the French or by us, and not by the Americans either.”

On Monday, French President Emmanuel Macron said the latest Russian bombardments “show the extent to which President Putin has lied to the Europeans and to the Americans.”