(CNN) — Former finance minister Rishi Sunak will be the United Kingdom’s next prime minister after seeing off his lone remaining rival in the fast-tracked race to become Conservative party leader on Monday.

The other potential candidate, Penny Mordaunt, conceded after failing to meet the threshold of nominations from lawmakers required to progress to the next stage of the race. Moments before the number of nominations were due to be announced, Mordaunt pledged her full support to Sunak.

Sunak will become the first person of color and the first Hindu to lead the UK. At 42, he is also the youngest person to take the office in more than 200 years.

He is set to replace Liz Truss, who will become the shortest-serving prime minister in UK history. Sunak will become prime minister once he is officially appointed by King Charles III and will be the first prime minister appointed by the new King following the death of Queen Elizabeth II in September.

Sunak officially declared he’d be standing on Sunday after securing the support of 100 Conservative lawmakers, the necessary threshold set by party officials. By Monday he had secured the support of more than half of the party’s 357 MPs.

“The United Kingdom is a great country but we face a profound economic crisis. That’s why I am standing to be Leader of the Conservative Party and your next Prime Minister. I want to fix our economy, unite our Party and deliver for our country,” he wrote on Twitter Sunday.

His campaign got a big boost when his former boss and rival, former Prime Minister Boris Johnson, withdrew from the race on Sunday night.

Monday marks the pinnacle of what has been an astonishingly quick rise to power for Sunak. He was first elected into Parliament in 2015 and became a junior minister in 2017. It was Johnson who gave Sunak his first major government role, appointing him as chief secretary to the Treasury in 2019 and promoting him to chancellor in 2020.

But as Britain’s third prime minister in seven weeks, Sunak is facing an enormous task.

His own party is divided and increasingly unpopular following four months of political turmoil and financial market chaos. At the same time, Britain is facing major economic crisis, with many economists believing it is already in recession.

Sunak, who also ran in the previous Conservative leadership contest over the summer, has not given any details on his planned policies in the past few days. During his leadership bid over the summer, he was seen as the more moderate of the two candidates.

He criticized Truss’ economic plan which ultimately sparked panic in the financial markets and led to her demise.

The-CNN-Wire
™ & © 2022 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.

This is a breaking story and will be updated.