US President Donald Trump says he has approved sending US defensive weapons to Ukraine and is considering additional sanctions on Moscow, underscoring his frustration with Russian President Vladimir Putin over the growing death toll in Russia’s war with Ukraine.

Trump, who pledged as a presidential candidate to end the war within a day, has not been able to follow through on that promise and efforts by his administration to broker peace have come up short.

Trump directed his ire at Putin on Tuesday (Wednesday AEST) during a meeting with cabinet officials at the White House.

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“I’m not happy with Putin. I can tell you that much right now,” Trump said, noting that Russian and Ukrainian soldiers were dying in the thousands.

“This is killing a lot of people.

“We get a lot of b******t thrown at us by Putin. ... He’s very nice all the time, but it turns out to be meaningless.”

Trump said he was considering whether to support a bill in the Senate that would impose steep sanctions on Russia over the war.

“I’m looking at it very strongly,” he said.

The bill, whose lead sponsors are Republican Senator Lindsey Graham of South Carolina and Democratic Senator Richard Blumenthal of Connecticut, would also punish other countries that trade with Moscow, imposing 500 per cent tariffs on nations that buy Russian oil, gas, uranium and other exports.

Trump said on Monday that the United States would send more weapons to Ukraine, primarily defensive ones, to help it defend itself against Russian advances. On Tuesday, he said he had approved such a move.

“We’re sending some defensive weapons to Ukraine, and I’ve approved that,” he said.

A decision by the Pentagon to halt some shipments of critical weapons to Ukraine prompted warnings by Kyiv last week that the move would weaken its ability to defend against Russia’s intensifying air strikes and battlefield advances.

Trump, who was seated next to Defense Secretary Pete Hegseth, was asked on Tuesday who had ordered that pause.

“I don’t know. Why don’t you tell me?” Trump responded.

-With AP