The new leader addressed the public shortly after the announcement pledging to serve the British people with integrity and humility.
"This is the greatest privilege of my life,' he said. "To be able to serve the party I love and give back to the country I owe so much to."
The former chancellor of the exchequer later said that the country faced "a profound economic challenge".
"We now need stability and unity," he declared. "And I will make it my utmost priority to bring our party and our country together.
"Because that is the only way we will overcome the challenges we face and build a better, more prosperous future for our children and our grandchildren.
- Rishi Sunak
The 42-year-old will replace Liz Truss, who announced her resignation after just six-weeks of being in the top job following her disastrous mini-budget caused division within her own party.
Mr Sunak is set to meet with King Charles at Buckingham Palace where he will be appointed Britain's 57th prime minister and asked to form government.
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