Sunak, favourite to replace the shortest-serving Prime Minister in UK history

British Prime Minister Liz Truss resigns

AP/ALBERTO PEZZALI - In the last few hours, the number of Conservative MPs calling for his resignation had soared, making his continuation as head of the executive virtually untenable

British Prime Minister Liz Truss announced her resignation as leader of the Conservative Party on Thursday and will step down as head of government as soon as her successor is chosen in an internal election next week.

"I recognise that, given the situation, I am unable to fulfil the mandate to which I was elected by the Conservative Party. I have spoken to His Majesty the King to tell him that I am resigning as leader of the Conservative Party," she said in a brief message outside her residence at 10 Downing Street.

Truss explained that this morning she met with the chairman of the 1922 Committee - which brings together Tory MPs without portfolio - Graham Brady, and both agreed that the internal election to appoint a successor should be held "next week". Until then, the Prime Minister will remain in office, she said.

Truss opened her statement with a reference to the "time of great economic and international instability" at which she came to office, which she assumed on 6 September after winning a party primary.

"We have delivered results on energy bills and lowering social security contributions. We have set out a vision for a low-tax, high-growth economy that would take advantage of the freedoms of Brexit," Truss said, before acknowledging that in the current situation she would not be able to meet his targets.

In the last few hours, the number of Conservative MPs calling for her resignation had shot up, making her continuity at the head of the Executive practically untenable.Truss had been in the doldrums since the presentation of her fiscal plan on 23 September, with a massive tax cut, had caused chaos in the markets and aroused mistrust in the British economy.

Rishi Sunak, the Finance Minister during the coronavirus pandemic, is emerging as the favourite to succeed Liz Truss as British Prime Minister, while Boris Johnson has begun to sound out the groundwork for a possible comeback just months after resigning amid scandals.

Sunak, 42, warned during last summer's Conservative primaries that Truss's fiscal plans would bring down the UK's finances, a warning that proved accurate and has given his allies the wings to claim him as the natural successor to the head of government, who announced her resignation on Thursday.

The former Finance Minister was also the candidate who won the most support among Tory MPs in the primaries, although he lost the last vote of the process, in which the party's rank and file opted for the aggressive tax cuts proposed by Truss to boost the economy.

The fall of the Conservative leader after only 45 days in Downing Street has led Johnson to raise with his close circle the possibility of standing as a candidate again, according to The Times.