Biden flubs during 1st State of Union, calls Ukrainians 'Iranian people'

US President Joe Biden appears to have made a gaffe during his maiden State of the Union speech, calling Ukrainians the "Iranian people" while urging them to stand united against the "unprovoked" Russian aggression.

In his widely-anticipated address on Tuesday night, Biden pledged to check Russian aggression in Ukraine, tame soaring US inflation and deal with the COVID-19 pandemic.

During his speech, Biden, while aiming for an inspiring moment of support against the Russian aggression, said to an awkward slow clap: "Putin may circle Kyiv with tanks, but he'll never gain the hearts and souls of the Iranian people."

"He'll never, he'll never extinguish their love of freedom," Biden said before someone yelled from the crowd.

Biden continued and added, "He (Putin) will never weaken the resolve of the free world, receiving thunderous applause and a standing ovation from the crowd.

At 79, Biden is the oldest sitting US President.

The moment quickly went viral online as videos were widely shared by political commentators like former Trump administration staffer Sebastian Gorka tagging it as an example of a #SenilePresident.

So far the incident has been viewed over 1 million times.

One clip appears to show Vice-President Kamala Harris mouth "Ukrainian" after Biden's blunder. The president has also faced criticism on social media for his error, the Newsweek reported.

Whether it was a stutter, gaffe or geographical confusion, Biden was already facing questions about his mental sharpness going into his first State of the Union, The Independent newspaper reported.

"Putin's war was premeditated and unprovoked. He rejected efforts at diplomacy. He thought the West and NATO wouldn't respond. And, he thought he could divide us here at home. Putin was wrong. We were ready, Biden said.

"Putin's war was premeditated and unprovoked. He rejected efforts at diplomacy. He thought the West and NATO wouldn't respond. And, he thought he could divide us here at home. Putin was wrong. We were ready, Biden said.

A new poll by ABC News/The Washington Post released on the eve of the speech found that 54 per cent of Americans don't believe he has the mental sharpness it takes to serve effectively as president.

According to the report, only 40 per cent believe Biden is mentally sharp enough for the job in a near-180-degree turnaround from 2020, when most Americans, 51 per cent, think he had the mental acuity for holding office compared to the 43 per cent who didn't.

The poll also found that 59 per cent of Americans do not think Biden is a strong leader, up from 49 per cent two years ago.