The forty-seven year old, who received 83% of the vote at the Democratic Alliance's national congress in Johannesburg, was running against the former mayor of Johannesburg, Mpho Phalatse, who would have been only the second Black leader in the party's history.

Steenhuisen will serve a three-year term as leader of the Democratic Alliance, which has historically appealed to a largely white demographic.

"During the remaining months before next year's election the DA will make it our number one priority ... to prevent an ANC-EFF coalition," Steenhuisen said in his victory speech, referring to the Economic Freedom Fighters, another left-leaning opposition party.

The Democratic Alliance was formed in 2003 after breaking away from parties that historically were part of the apartheid government. It became the official opposition following the 2004 general elections and steadily grew its support until 2019, where it suffered its first decline in a national election under the leadership of Mmusi Maimane, its first Black leader.

The party has managed to maintain control of the Western Cape province and in the 2021 local government elections it won mayoral positions, through coalition governments, in three key cities across South Africa.

But coalitions have proven difficult to manage and the DA has had all three of its mayoral candidates ousted since 2021. Steenhuisen conceded that the coalitions to date had been "unstable" and announced plans to lead a pre-election united opposition "Moonshot Pact" consisting of opposition parties and civic organisations.

During the 2021 elections, the ruling ANC fell below the 50% threshold for the first time in democratic history. The DA won 20% of the vote, compared with 24.6% five years before, losing votes to the EEF.

(Reporting by Kopano Gumbi; Editing by David Holmes)