CANBERRA, Aug. 24 (Xinhua) -- Incoming Australian Prime Minister Scott Morrison has flagged the nation's drought as his number one priority.

Morrison defeated conservative colleague Peter Dutton in a ballot on the leadership of the governing Liberal Party of Australia by 45 votes to 40 on Friday after Foreign Affairs Minister and deputy leader Julie Bishop was eliminated in the first round of voting having received the fewest votes.

Morrison, who served as Australia's Treasurer under Malcolm Turnbull, will become Australia's 30th prime minister and the sixth since 2007.

Speaking at his first press conference after winning the ballot, Morrison described the drought, which is Australia's worst in 50 years, as his "most urgent and pressing issue."

"As soon as possible, I will review our drought response plans... to ensure that we do what is necessary to help our regional communities, our farmers, and all those affected," he told reporters in Canberra.

"That will be my first focus, but there are many others.

"That's what matters. We are on your side. And we are on your side because we share beliefs and values in common, as you go about everything you do each day.

"We will provide the stability and the unity and the direction and the purpose that the Australian people expect of us as leaders."

He thanked Turnbull for his "noble and professional" service as prime minister and confirmed that Bishop would be offered a ministerial position.

Josh Frydenberg, who served as Energy and Environment Minister under Turnbull, was elected as Morrison's deputy leader after defeating Health Minister Greg Hunt and Trade Minister Steven Ciobo in the ballot and will succeed Morrison as treasurer.

The result was a surprise after Dutton, who resigned as Home Affairs Minister after being defeated by Turnbull 48-35 in a leadership ballot on Tuesday, spent most of the week as the candidate considered most likely to topple Turnbull.

Turnbull's decisions to delay the second ballot until Friday and step aside to allow Morrison and Bishop, two of his biggest supporters in the party room, to run as moderate candidates proved fatal for Dutton.

Speaking after the ballot, Dutton pledged "absolute loyalty to Scott Morrison."

Turnbull confirmed on Friday that he would resign from parliament "before too long," ending 14 years as a parliamentarian.

"It has been such a privilege to be the leader of this great nation," he told reporters in his last press conference as prime minister.