"Thank you to everyone who voted for me in this campaign. 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," Sunak said on Twitter.
Earlier in the day, it was announced that Truss had won the Conservative Party leadership race and would become the new prime minister of the United Kingdom on Tuesday.
On July 7, Boris Johnson, who succeeded Theresa May as UK prime minister in 2019, announced his resignation.
In total, 11 lawmakers initially declared their desire to participate in the prime minister election race. Truss and Sunak were the two final candidates in the race and during the last round, the winner was chosen by all members of the party, which is around 200,000 people.