'What the hell happened to him?' Trump criticises Putin after deadly strikes across Ukraine

Donald Trump has threatened Russia with more sanctions after a series of deadly strikes across Ukraine, as he said of Vladimir Putin: "What the hell happened to him?"

The US president appeared aghast at the conduct of his counterpart in the Kremlin after drone attacks in Kyiv and other Ukrainian cities left 12 people dead and dozens more injured.

Trump criticises Putin - latest updates

Speaking to reporters at an airport in New Jersey ahead of a flight back to Washington, Mr Trump said: "I'm not happy with Putin. I don't know what's wrong with him."

"He's killing a lot of people," he added. "I'm not happy about that."

Mr Trump - who said he's "always gotten along with" Mr Putin - told reporters he would consider more sanctions against Moscow.

Ukraine said the barrage of strikes overnight into Sunday was the biggest aerial attack of the war so far, with 367 drones and missiles fired by Russian forces.

It came despite Mr Trump repeatedly talking up the chances of a peace agreement. He even spoke to Mr Putin on the phone for two hours last week.

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'Shameful' attacks

Volodymyr Zelenskyy has said Ukraine is ready to sign a ceasefire deal, and suggested Russia isn't serious about signing one.

In a statement after the latest attacks on his country, he urged the US and other national leaders to increase the pressure upon Mr Putin, saying silence "only encourages" him.

Mr Trump's envoy for the country, Keith Kellogg, later demanded a ceasefire, describing the Russian attacks as "shameful".

Three children were among those killed in the attacks, explosions shaking the cities of Kyiv, Odesa, and Mykolaiv.

Before the onslaught, Russia said it had faced a Ukrainian drone attack on Sunday. It said around 100 were intercepted and destroyed near Moscow and in central and southern regions.

The violence has escalated despite Russia and Ukraine completing the exchange of 1,000 prisoners each over the past three days.