Britain is set to have its first prime minister of Asian background.

Former Treasury chief Rishi Sunak was the only candidate to secure the backing of 100 Conservative MPs needed to be nominated.

Conservative Party 1922 Committee chair, Graham Brady said, "I can confirm that we have received one valid nomination. And Rishi Sunak is therefore elected as Leader of the Conservative Party."

The 42-year-old Sunak has been the frontrunner since Liz Truss resigned last week. He will be Britain's third prime minister in less than two months.

Media reports say Sunak became wealthy during his career in finance before entering politics in 2015.

Fixing the economy will be a major priority. He is expected to introduce deep spending cuts to rebuild Britain's fiscal reputation.

His rival, House of Commons Leader Penny Mordaunt, withdrew from the race in the final minutes.

Sunak's former boss, Boris Johnson, pulled out, saying his return wouldn't be "right," suggesting the Conservative Party wouldn't unite behind him.

Sunak will also have to rebuild trust in the party. Recent polls suggest it is trailing far behind the Labour opposition.