'It was awful!' Biden's gaffe has ruined months of hard work and undermined Nato summit, say European officials

He later accidentally named his Vice President as Republican rival Donald Trump rather than running-mate Kamala Harris.

European officials were particularly critical of the 46th President after his mistakes.

“It was awful,” an anonymous official told The Telegraph.

Another insider said: “It’s taken the focus away from what has been a great summit for us.”

However, Nato allies have outwardly defended the 46th President, who is facing calls to quit ahead of November 5, over his “slip of the tongue”.

French President Emmanuel Macron and German Chancellor Olaf Scholz defended Biden, describing the Commander-in-Chief as someone “who is in charge” and “clear on the issues he knows well”.

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Sir Keir Starmer also said: “I would urge everyone to look at the substance of what’s been achieved over these two days.”

The Prime Minister, who dismissed concerns about Biden being senile, added: “When we think of the global threats, that is the best possible outcome we could have had today and so I think he deserves credit for that, as does the team that worked with him.

“We close this council with renewed confidence and resolve to meet the challenge of Russian aggression.

“That is the outcome we all hoped we would get to and President Biden led us through that.”

Nato sources believed Biden’s slip-up took away from the significant progress made by the defence bloc.

A new announcement confirmed that 23 of its 32 states had hit the spending goals of 2 per cent of GDP on defence.

Zelensky was also reportedly leaving Washington satisfied with the levels of support shown to Ukraine.

However, Biden’s blunders also continue to heap pressure on the 46th President ahead of his re-election battle against Trump on November 5.

A Republican strategist, who was previously critical of Trump’s chances, told GB News: “Trump, as it stands now, will beat Biden.

“Biden had yet another disastrous conference last night with Nato. It was awful.”

Trump posted a series of updates on his social media platform Truth Social laying into his White House successor.

“Crooked Joe has a case of Trump Derangement Syndrome,” the 45th President wrote.

Trump met with Hungarian Prime Minister Viktor Orban to discuss events in Ukraine as other leaders met in Washington.

Biden defiantly reassured Democrats he would take on Trump later this year.

In a letter to Democratic figures in Washington, the 81-year-old wrote: "I want you to know that despite all the speculation in the press and elsewhere, I am firmly committed to staying in this race, to running this race to the end, and to beating Donald Trump."

Biden added: "I can respond to all this by saying clearly and unequivocally: I wouldn't be running again if I did not absolutely believe I was the best person to beat Donald Trump in 2024."

Biden separately claimed losing is "not an option" and stressed he is getting "frustrated by elites" in the Democratic Paty calling for him to quit.

Despite the public turning towards Trump during the heated exchange, opinion polls suggest Biden remains better placed than Harris to take on the ex-President.

JL Partners revealed 47 per cent of voters currently support Trump, with just 42 per cent backing Biden.

However, Trump's vote share increases to 49 per cent against Harris, with the Vice President slumping to as low as 38 per cent.

Dropping out of the 2024 race at this stage would see Biden become the first Commander-in-Chief since Lyndon B Johnson to not seek re-election.

Despite his blunders in Washington, a Biden donor said: "This is the person who can beat Trump. The mistakes are baked in and the upside is strong."