Nancy Pelosi has announced her retirement from Congress, ending a decades-long career that saw the California Democrat become one of the most powerful figures in US politics.

In a video message on Thursday, Pelosi said she will not be seeking re-election to Congress at the end of her term in January 2027.

It marks the end of a storied political career: Pelosi, 85, became the first woman to serve as Speaker of the House and led her party in the lower chamber of Congress from 2003 until 2023.

"We have made history, we have made progress," Pelosi said in her message.

"We have always led the way, and now we must continue to do so by remaining full participants in our democracy, and fighting for the American ideals we hold dear."

"As we go forward, my message to the city I love is this: San Francisco, know your power," Pelosi added.

Pelosi was first elected to Congress to represent San Francisco in 1987 aged 47, and quickly rose through the ranks.

She was elected by her party to be speaker of the House in 2007, becoming the first woman to serve in that role. She served until 2011, when Democrats lost control of the lower chamber, before returning to the speaker's chair from 2019 to 2023.

Speaker of the House is the one congressional job detailed in the US Constitution. After the vice-president, it is next in line to the presidency.

In that role, Pelosi played a critical role in advancing - or thwarting - the agendas of multiple presidents during her long career on Capitol Hill.

She is widely credited with marshalling the passage of former President Barack Obama's signature healthcare legislation, as well as bills to address infrastructure and climate change during Joe Biden's presidency.

Pelosi also directly challenged Donald Trump throughout his presidency, famously ripping up a copy of his State of the Union address behind his back.

By then she was also a lightning rod for Republican anger - in their eyes, representing the coastal elites pushing a big-spending, radical platform.

She led two impeachment efforts against Trump - the first in 2019 over his dealings with Ukraine. Trump was accused of pressing Ukraine to dig up damaging information on Biden, and of using military aid as leverage. He was later acquitted in the Republican-controlled Senate.

The second was in 2021, when he was accused by the House of inciting the storming of the Capitol - the seat of the US Congress - with a speech on 6 January to supporters outside the White House. That effort ultimately failed, and Trump was acquitted once again.

On Thursday, when asked about Pelosi's retirement, Trump said she was "an evil woman".

"I'm glad she's retiring. I think she did the country a great service by retiring," he told reporters in the Oval Office. "I think she was a tremendous liability for the country."

After Trump's first term, Pelosi worked with Biden to shepherd much of his legislative agenda through her chamber despite the razor-thin margins.

In less than two years, Democrats in the House pushed through a Covid relief bill, a bipartisan infrastructure spending package, a multi-trillion-dollar environment and social spending programme, and legislation protecting gay marriage.

She was succeeded as Democratic leader in the House by New York Representative Hakeem Jeffries in 2022.

Since leaving her speakership, she has remained a major political influence. Most recently, she played a key role in helping to pass Proposition 50 in California - a state redistricting effort aimed at flipping five House seats to Democrats during the midterms in 2026.