US House Speaker Nancy Pelosi has announced that she will not seek reelection to the Democratic Party’s congressional leadership after Republicans narrowly regained control of the chamber.

Pelosi, 82, who in 2007 became the first woman to serve as the speaker, has been the top House Democratic lawmaker for nearly 20 years. On Thursday, she said she would continue to serve in Congress to represent her constituents in California, but she is ready to pass the leadership torch to the younger generation.

Her decision comes less than a month after an intruder assaulted her husband at the couple’s home in San Francisco in what US authorities say was a politically-motivated attack.

“With great confidence in our caucus, I will not seek reelection to Democratic leadership in the next Congress,” Pelosi said in a speech on the House floor. “For me, the hour has come for a new generation to lead the Democratic caucus that I so deeply respect, and I’m grateful that so many are ready and willing to shoulder this awesome responsibility.”

Democrats will elect their leaders for the new Congress, which convenes early next year, at the end of the month. House Democratic Conference Chairman Hakeem Jeffries, a 52-year-old New York representative, is widely considered a frontrunner to replace Pelosi.

The top three Democrats in the House – Pelosi, House majority leader Steny Hoyer and majority whip Jim Clyburn – are in their 80s.

Hoyer also announced in a letter to Democratic lawmakers on Thursday that he will not seek a leadership position in the next Congress, saying that it was time for a “new generation of leaders”. Clyburn, too, suggested that he will leave his position as whip.

“Speaker Pelosi has left an indelible mark on Congress and the country, and I look forward to her continued service and doing whatever I can to assist our new generation of Democratic Leaders which I hope to be Hakeem Jeffries, Katherine Clark, and Pete Aguilar,” Clyburn wrote in a tweet.

In her speech on Tuesday, Pelosi warned about the fate of US democracy, citing the January 6, 2021 attack on the Capitol by supporters of former President Donald Trump who sought to prevent the certification of President Joe Biden’s 2020 election victory.

“American democracy is majestic, but it is fragile,” Pelosi said. “Many of us here have witnessed this fragility firsthand – tragically in this chamber. And so, democracy must be forever defended from forces that wish it harm.”

She expressed gratitude her husband, who was attacked by a hammer last month ahead of the elections, fuelling fears of political violence. “For my dear husband, Paul, who has been my beloved partner in life and my pillar of support: Thank you. We’re all grateful for all the prayers and well-wishes as he continues his recovery,” she said to a standing ovation from a nearly full House.

Speaker Nancy Pelosi is the G.O.A.T.

Thank you for all that you have done for America.

— Hakeem Jeffries (@RepJeffries) November 17, 2022

Biden called Pelosi the “most consequential” House speaker in US history.

“Because of Nancy Pelosi, the lives of millions and millions of Americans are better, even in districts represented by Republicans who voted against her bills and too often vilify her. That’s Nancy – always working for the dignity of all of the people,” the US president said in a statement on Thursday.

The daughter of a former US congressman and Baltimore mayor, Pelosi has been serving in the House since 1987 – before some current members of her caucus were born.

The outgoing House speaker is often praised as an effective lawmaker who managed to keep unity in a Democratic caucus that is far from ideologically homogeneous.

During her two stints as speaker – from 2007 to 2011 and 2019 until the end of the year – she passed historic legislation, including former President Barack Obama’s healthcare reform law, the Affordable Care Act.

US lawmakers were quick to pay tribute to Pelosi on Thursday, praising her leadership and years of service.

“Nancy Pelosi is a trailblazer. A fierce advocate for California and our entire country, she was fearless in the face of impeachments and insurrection. Her legacy will live on with our next generation of leaders,” House Democrat Katie Porter wrote on Twitter.

Senator Chris Van Hollen said Pelosi made history as the first female speaker of the House but also offered the most effective leadership.

“She has been the fearless force behind much of the progress we have made in the 21st Century. Her legacy is forever etched in American history,” Van Hollen said in a social media post.

Over her career, Pelosi has been criticised from the left for not pushing more progressive legislation and failing to back impeaching former President George W Bush over the Iraq invasion and torture of prisoners after the 9/11 attacks.

And Republicans have vilified Pelosi as a symbol of everything they dislike about Democrats: a member of the so-called “coastal elite” who supports higher taxation and government spending.

Ahead of the midterm vote, “firing Nancy Pelosi” became a rallying cry for Republicans. Despite an underwhelming election performance where they failed to capture the Senate, Republicans were able to narrowly take back the House, ensuring that Pelosi would not serve for another term as speaker.

Although the president is largely responsible for US foreign policy, in her decades-long career, Pelosi has stepped into the international limelight.

Earlier this year, she angered China by visiting Taiwan. She also oversaw the allocation of continuing US aid to Ukraine after the Russian invasion and travelled to Kyiv where she met with Ukrainian President Volodymyr Zelenskyy in May.

The outgoing speaker is a staunch supporter of Israel. “If this Capitol crumbled to the ground, the one thing that would remain would be our commitment to our aid – I don’t even call it our aid – our cooperation with Israel. That’s fundamental to who we are,” she said in 2018.