• The prime minister is under intense pressure to step down after U-turning on her "mini-budget."
• However, she told the House of Commons she was a "not a quitter" as she was questioned by politicians.
• Any resignation leaves open the question of who would succeed her and what direction they would take the fractured party in.

LONDON — British Prime Minister Liz Truss insisted Wednesday she was a "fighter not a quitter" as she was grilled by parliamentarians for the first time since being forced to scrap almost all of her flagship fiscal policies.

Truss said she had "acted in the national interest to make sure that we have economic stability," while also starting the session by saying she was "sorry" and had "made mistakes."

The row-back of her huge program of tax cuts, originally announced on Sept. 23, came after it sparked massive volatility in financial markets, with the pound plunging against the dollar and U.K. government bonds being sold off at such a rapid rate it threatened to topple pension funds. Mortgage deals were also pulled as interest rate hike expectations rose rapidly.

Full details of the government's new economic policies are expected Oct. 31, along with an independent economic forecast.

Attack lines from opposition leader Keir Starmer during Prime Minister's Questions on Wednesday included questions over how the public could trust a leader whose "promises didn't last a week"; branding her policies "fantasy economics"; and accusing Truss of crashing the economy.

"I had to take the decision because of the economic situation to adjust our policies," Truss said. She added that interest rates were rising globally and economic forecasts had worsened.

Analysts told CNBC bond markets were being influenced by a range of factors and may recover, but the U.K. had suffered long-term damage to its economic credibility.

Pressure to resign

The turbulence over the last month has left Truss under intense pressure to resign less than two months into her tenure, even from members of her own party.

Speculation currently abounds over her future, including whether she could step down — with the Conservative Party plunging in opinion polls and a recent YouGov survey putting Truss' popularity at just 10% — or be forced out.

Under current party rules, the Conservatives are not able to oust Truss and hold another leadership election for a year. Truss went head-to-head against former Finance Minister Rishi Sunak for two months over the summer after ex-PM Boris Johnson resigned in July.

However, the party could agree on a replacement if she were to step down, or it could look to alter current rules.

Both options would likely prove divisive, with the party also split on the best successor. Contenders are thought to include new Finance Minister Jeremy Hunt; Sunak; Leader of the Commons Penny Mordaunt, who stood in for Truss earlier this week; and even a return of Johnson.

It may also leave the party facing further pressure to hold a general election to provide it with a public mandate. The last vote was held on Dec. 12 2019, when Johnson led the Conservatives to a landslide majority.

Meanwhile, a vote called by the opposition Labour Party to be held later Wednesday on reinstating the U.K.'s ban on fracking was described in a leaked Conservative Party email, published by Sky News, as a "confidence motion in the government."

Many Conservative MPs oppose fracking, which was only re-permitted last month.