The Foreign Secretary beat Rishi Sunak in the Conservative leadership contest. As a result, she will succeed Boris Johnson as the next British prime minister.
Liz Truss has been elected as the new leader of the Conservative Party and will become Britain's new prime minister, party officials announced on Monday.
She will take over from Boris Johnson who announced his resignation in July following a slew of scandals and resignations from his government.
Truss, the current Foreign Secretary, was given the mandate to lead the country by the governing party's members after a grueling six-week campaign against former Finance Minister, Rishi Sunak.
She and Johnson will travel to Scotland on Tuesday to meet Queen Elizabeth II for the official handover of power.
What will the prime minister need to address first?
Truss promised to "deliver a bold plan to cut taxes and grow the economy."
She faces "the worst in-tray for a new prime minister since Thatcher," The Sunday Times wrote, referencing former Prime Minister Margaret Thatcher.
Top of the list will be tackling the United Kingdom's cost-of-living crisis.
Thanks to global gas price volatility triggered by the war in Ukraine, the average UK household energy bill is jumping to more than 3,500 pounds ($4,000; €4,041) a year. The UK faces decades-high inflation and is tipped to enter recession later this year.
Truss on Sunday promised to take "decisive action to ensure families and businesses can get through this winter and the next."
"If elected, I plan within the first week of my new administration to set out our immediate action on energy bills and energy supply," she wrote in the Sunday Times.
She declined to comment on a report that her energy plan could exceed 100 billion pounds, but the lawmaker tipped to be her finance minister, business minister Kwasi Kwarteng, wrote on Monday that the government could afford to borrow more to fund support for households and businesses.
Truss has also signaled during her leadership campaign that she would challenge convention by scrapping tax increases and cutting other levies.
What foreign policy issues face the UKs new leader?
The new prime minister will also have to steer the UK on the international stage with Russia's war in Ukraine, an increasingly assertive China, and ongoing tensions with the European Union over the aftermath of Brexit toping that agenda.
Truss, said she would tear up parts of the Northern Ireland Protocol, a step that could lead to a trade war with the EU.
A bill to unilaterally scrap some customs checks to ease the movement of goods is working its way through the British parliament, and Truss said last month that if picked as prime minister she would seek to deliver that legislation in full.
Sunak, has said he would "push on" with the legislation while still trying to negotiate with the EU.
