Sunak, 42, soon after his defeat, took to Twitter to thank everyone who voted for him and urged all to support Truss as she "steers the country through difficult times".

"I've said throughout that the Conservatives are one family. It's right we now unite behind the new PM, Liz Truss, as she steers the country through difficult times," the British Indian former Chancellor tweeted.

Truss has won over 80,000 votes as compared to 60,000 odd votes bagged by Sunak.

"I am honoured to be elected Leader of the Conservative Party. Thank you for putting your trust in me to lead and deliver for our great country.

"I will take bold action to get all of us through these tough times, grow our economy, and unleash the United Kingdom’s potential," Truss tweeted.

Truss will formally become the Prime Minister Tuesday after visiting the Queen in Balmoral in Scotland for an invitation to form the government.

Speaking shortly after her victory was announced in Westminster, Truss thanked Sunak and others for the "hard-fought" campaign in the leadership race.

Truss said she has a "bold plan" to cut taxes and grow the country's economy, BBC reported.

"We will deliver, we will deliver, we will deliver," said the PM-elect.