Joe Biden’s slowness in exiting the 2024 presidential election cost the Democrats dearly, the former House speaker Nancy Pelosi said, days after Kamala Harris was beaten by Donald Trump.

“We live with what happened,” Pelosi said.

Pelosi was speaking to The Interview, a New York Times podcast, in a conversation the newspaper said would be published Saturday in full.

“Had the president gotten out sooner,” Pelosi remarked, “there may have been other candidates in the race. The anticipation was that, if the president were to step aside, that there would be an open primary.

“And as I say, Kamala may have, I think she would have done well in that and been stronger going forward. But we don’t know that. That didn’t happen. We live with what happened. And because the president endorsed Kamala Harris immediately, that really made it almost impossible to have a primary at that time. If it had been much earlier, it would have been different.”

As Democrats engaged in bitter blame games over Harris’s defeat and a second presidency for Trump, who senior Democrats from Harris down freely called a “fascist”, Pelosi’s words landed like an explosive shell.

The Times said Pelosi “went to great lengths to defend the Biden administration’s legislative accomplishments, most of which took place during his first two years, when she was the House speaker”.

Republicans took the House in 2022. Pelosi, now 84, was re-elected this week to a 20th two-year term.

Biden was 78 when elected in 2020 and is now just short of 82. He long rejected doubts about his continued capacity for office, but they exploded into the open after a calamitous first debate against Trump, 78, in June.

On 21 July, the president took the historic decision to step aside as the Democratic nominee. Within minutes, he endorsed Harris to replace him.

Pelosi reportedly played a key role in persuading Biden to stand aside. But she has not sought to soothe his feelings. In August, she told the New Yorker she had “never been that impressed with his political operation”.

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She said: “They won the White House. Bravo. But my concern was: this ain’t happening, and we have to make a decision for this to happen. The president has to make the decision for that to happen.”

Biden is widely reported to be furious with the former speaker. This week, reports have said the president and his senior staffers are furious with Barack Obama, under whom Biden served as vice-president but who also helped push Biden to drop out of the re-election race.

According to the Times, Pelosi also rejected comments from Bernie Sanders in which the independent senator from Vermont said Trump won because Democrats “abandoned working-class people” – remarks the chair of the Democratic National Committee, Jaime Harrison, called “straight-up BS”.

“Bernie Sanders has not won,” Pelosi said. “With all due respect, and I have a great deal of respect for him, for what he stands for, but I don’t respect him saying that the Democratic party has abandoned the working-class families.”

According to Pelosi, cultural issues pushed American votes to Trump.

“Guns, God and gays – that’s the way they say it,” she said. “Guns, that’s an issue. Gays, that’s an issue. And now they’re making the trans issue such an important issue in their priorities, and in certain communities, what they call God, what we call a woman’s right to choose” regarding abortion and other reproductive care.