In her resignation statement outside Downing Street on Thursday, Liz Truss promised that a fresh leadership election will be held within a week.
The contenders to succeed Truss will require at least 100 nominations from Conservative MPs, according to Graham Brady, the officer in charge of the process inside the Conservative Party.
In the event that more than one candidate passes that requirement, the Conservative members will vote online to choose the new prime minister, who will be inaugurated on Friday, October 28.
This will be the third Conservative prime minister during this legislative session and the fifth in just over six years. But who may be the new ruler? Some of the top runners and riders are listed below:
Rishi Sunak
Given that many of the prophecies Sunak made regarding Truss's economic strategy during this summer's leadership came true, he has become as something of a government-demise prophet.
A run on the pound, a panic in the bond market, and alarm from the IMF were all predicted by the former Chancellor of the Exchequer (finance minister) in response to Truss's unfunded tax cuts. Perhaps even he would have been taken aback by how quickly he was vindicated.
Sunak has expertise in managing financial crises after leading the UK during the Covid-19 outbreak.
In the previous leadership election, he likewise received the highest support from MPs, handily surpassing the new bar with 137 votes. Sunak lost by a razor-thin margin, with 43% of the vote, even though Truss ultimately received the crucial member vote.
He may be the most probable candidate to take the helm as the next pair of hands because of the respect he enjoys among MPs and the validation his forecasts have received.
Penny Mordaunt
After filling in for an absent Liz Truss during a discussion, the Leader of the House of Commons may have had a dress rehearsal for being prime minister this week.
In a presentation that appeared to be more about promoting herself than it did about supporting the PM, Mordaunt stated on Tuesday that "the prime minister is not beneath a desk."
Mordaunt nearly missed being presented to the members by placing third in the most recent leadership election. She is also anticipated to pass the newt threshold with 105 votes from MPs in the most recent election.
Due in part to her military experience, she is anticipated to do well among the party members. Mordaunt, a member of the Royal Navy Reserve, formerly held the position of Secretary of State for Defense.
She comes from the more moderate section of the party, like Sunak. Even among MPs, there was discussion of the two creating a "dream team" ticket, but this hasn't happened and it's not obvious if each would prefer becoming chancellor to holding the top position.
Kemi Badenoch
Despite receiving just 59 votes from MPs and finishing fourth in the leadership race this summer, Badenoch was regularly regarded by pollsters as a favorite among grassroots Conservative members.
One of the more recent candidates for the position of MP, Badenoch rapidly gained the support of longtime Tory grandee Michael Gove, who hailed her as the party's "exceptional potential."
The conservative Badenoch had argued that the government's climate ambitions would be too expensive during her candidacy for the party's leadership.
Now that Truss's MP votes are up for grabs, Badenoch may have a remote possibility of passing the requirement and moving on to the members' vote.
Grant Shapps
Grant Shapps' elevation to home secretary during Truss's final days in power, despite the fact that she had never given him a ministerial position of any kind, is a sign of the chaos in her administration.
Shapps was Boris Johnson's transport secretary. In the last leadership election, he ran to replace him but withdrew three days later after failing to receive the necessary 20 MP votes to advance to the next round.
The new bar will probably be too high for Shapps, although his early criticism of Truss' administration may have gained him the backing of more MPs than in the previous election.