Joe Biden has said the world must stand up to Russia’s “naked aggression” and support the people of Ukraine.
Speaking to the UN General Assembly, he said Moscow alone bears responsibility for the war, stands in the way of peace, and has the power to end the conflict immediately.
The US president urged UN members to continue supporting Ukraine – as failure to do so will allow Russia to brutalise the country without compromise.
Mr Biden said: “If we allow Ukraine to be carved up, is the independence of any nation secure? I respectfully suggest the answer is no – we have to stand up to this naked aggression today and deter the would-be aggressors of tomorrow.”
He vowed that the US “will continue to stand with the brave people of Ukraine as they defend their sovereignty, territorial integrity and freedom”.
The president’s remarks attracted applause from UN delegates – including his Ukrainian counterpart Volodymyr Zelenskyy, who was in the audience.
On Tuesday, UN Secretary-General Antonio Guterres had warned that Russia’s invasion “has unleashed a nexus of horror”.
But back in Washington, Mr Biden has faced criticism from Republicans who want the US to spend less money on the war effort – with Donald Trump vowing to seek a quick end to the conflict if he is re-elected in the 2024 presidential election.
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‘An existential threat’
In a wide-ranging speech, Mr Biden warned the world is at an “inflection point in history” – and no nation can meet the challenges of today alone.
“Our future is bound to yours,” he said.
One area of focus was climate change – with the US president telling delegates it is “critical” to decelerate the crisis.
“We see it everywhere – record-breaking heatwaves in the US and China, wildfires ravaging North America and southern Europe, a fifth year of drought in the Horn of Africa,” he said.
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Furious crowds call for justice in Libya
Mr Biden also pointed to “tragic, tragic” flooding in Libya that has killed thousands of people – and said his heart goes out to those who have been displaced.
“Together, these snapshots tell an urgent story of what awaits us if we fail to reduce our dependence on fossil fuels and begin to climate-proof the world,” he added.
The US president went on to say that his administration has treated the climate crisis as an existential threat from the day he took office – “not only for us, but for all of humanity”.
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Is AI an existential threat?
On China and artificial intelligence
Mr Biden told the UN General Assembly in New York that “AI holds enormous potential and enormous peril” – and the world needs to ensure they are used as “tools of opportunity, not weapons of oppression”.
He added: “The US is working to strengthen rules and policies so AI technologies are safe before they’re released to the public.”
The president said world leaders need to make sure they are governing this technology, rather than the other way around.
And on China, Mr Biden stressed that he wants to responsibly manage competition between both countries to prevent tensions tipping into conflict.
“We are for derisking, not decoupling with China,” he said. “We will push back on aggression and intimidating and protect the rules of the road. We also stand ready to work together with China where progress hinges on our common efforts.”