British Prime Minister Liz Truss announced her resignation Thursday, just over six weeks into the nation's top job after a political crisis caused by her economic plans increasingly undermined her premiership and authority.

Truss, Britain's third female prime minister, said she is resigning as leader of the ruling Conservative Party to preserve economic stability, with a new leader expected to be chosen through a leadership contest by the end of next week.

Truss, who will remain in her job until a new leader is chosen, is likely to be remembered as the shortest-serving prime minister in British history.

"We set out a vision for a low tax, high growth economy that would take advantage of the freedoms of Brexit," the prime minister said outside her 10 Downing Street office. "I recognize, though, given the situation, I cannot deliver the mandate on which I was elected by the Conservative Party."

British Prime Minister Liz Truss announces her resignation at Downing Street on Oct. 20, 2022, in London. (Getty/Kyodo)

U.S. President Joe Biden apparently sought to play down the impact of the British leader's abrupt resignation on their bilateral ties, saying in a statement that the two countries are "strong allies and enduring friends -- and that fact will never change."

Truss became prime minister on Sept. 6, taking the reins from Boris Johnson, who stepped down following a wave of resignations triggered by a series of scandals that cast his integrity into question.

Truss has presided over plummeting approval ratings and polling for her party since her then finance minister Kwasi Kwarteng announced the government's mini-budget fiscal plan on Sept. 23.

Its tax-cutting measures brought chaos to government bond and currency markets, which took fright at the black hole such policies would inflict on government finances while sparking division within the party over who should lead the government.

To stem the backlash, Truss first dismissed Kwarteng on Friday and installed former Foreign Secretary Jeremy Hunt, and on Wednesday accepted the resignation of Home Secretary Suella Braverman, replacing her with Grant Shapps. Neither Hunt nor Shapps has supported the prime minister's economic agenda.

The moves, intended to introduce stability to Truss' flagging government, instead dropped her into greater turmoil as questions over her fitness for the job swirled in her party and across the country.

In the days after his appointment, Hunt largely withdrew Truss' economic pledges. A survey by pollster YouGov on Wednesday showed that 46 percent of respondents believed Hunt to be in charge of government policy.

Braverman's departure was no less damaging, and she eschewed the measured tones of a typical resignation letter to express concern about the government's direction, saying it had "broken key pledges that were promised to our voters."

During Prime Minister's Questions in the House of Commons on Wednesday, Truss shot back at Labour Party barbs over her position by saying she was "a fighter, not a quitter." But the newspaper front pages the following morning focused on the disruption, including from Braverman's departure, with many describing the government as in chaos.

Truss, 47, defeated Rishi Sunak, a former chancellor of the exchequer, in the leadership race caused by Johnson's resignation. Truss was appointed by Queen Elizabeth two days before the monarch died. Truss led the country in mourning and spoke at the late queen's funeral in Westminster Abbey.

Local media has begun speculating who might replace Truss, with a comeback from Johnson just months after he resigned a possibility. Currently, the other contenders are Sunak and Penny Mordaunt, the leader of the House of Commons.

Bookmakers have Sunak as favorite at over a 50 percent probability, according to the conservative-leaning Telegraph newspaper, with Mordaunt and Johnson neck and neck at around 20 percent.

Before becoming prime minister, Truss was foreign secretary and had held a series of Cabinet appointments.

Currently, Britain's shortest-serving prime minister is Tory statesman George Canning, who spent 118 full days as prime minister in 1827 before dying in office from ill health, according to the British news agency PA Media. Truss is set to eclipse that record.

Biden in his statement thanked Truss for her partnership on a range of issues including holding Russia accountable for its war against Ukraine.

"We will continue our close cooperation with the U.K. government as we work together to meet the global challenges our nations face," he added.


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