Former President Joe Biden told BBC Radio he doesn't regret staying in the 2024 presidential race as long as he did because "I don’t think it would have mattered."

Biden stepped down as the Democratic Party’s nominee, under pressure from party leaders, following his disastrous performance against Donald Trump in a televised June debate. Vice President Kamala Harris proceeded to lose handily to Trump in the November election despite Democrats holding a significant financial advantage.

In his first in-depth interview since leaving the White House in January, Biden claimed to BBC Radio's Nick Robinson that his decision about whether to remain in the race or bow out "difficult" due to his term being "so successful."

"I don’t … I don’t think it would have mattered," he told Robinson after being asked whether he should have withdrawn from the race earlier. "We left at a time when we’re … we had a good candidate. She was fully funded. Um, and what happened was, I had become … what we had set out to do, no one thought we could do. I’d become so successful on our agenda, it was hard to say, Now I’m gonna stop now.

"I meant what I said when I started that I think … I’m preparing to hand this to the next generation, the transition government. But it … things moved so quickly that it made it difficult to walk away. And, uh, it was a … it was a hard decision."

Asked whether he had regrets, Biden said: "No, I think it was the right decision. I think that  … well, it was just a difficult decision."

Biden spent much of the interview trashing his successor's foreign policy initiatives.

He described the Trump administration's suggestion that Ukraine give up territory as part of a peace deal with Russian President Vladimir Putin as "modern-day appeasement."

"I just don't understand how people think that if we allow a dictator, a thug, to decide he's going to take significant portions of land that aren't his, that that's going to satisfy him,” Biden said. "I don't quite understand."

Biden said he had "grave concern" about the future of NATO because Trump has said all partners should pay their fair share for defending Europe.

"I think it would change the modern history of the world if that occurs," he said. "We are not the essential nation, but we are the only nation in position to have the capacity to bring people together to lead the world."

Biden also criticized Trump for scolding Ukrainian President Volodymyr Zelenskyy, and for expressing that the U.S. take control of Canada, Greenland and the Panama Canal.

"What president ever talks like that?" Biden said. "That's not who we are. We're about freedom, democracy, opportunity, not about confiscation."

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