South Africans awaited confirmation on Sunday of a historic election outcome that will dismantle a 30-year African National Congress (ANC) majority, an announcement that will start the clock on a frenzied race to form a new ruling coalition.

Voters, angry at joblessness, inequality and power shortages, slashed support for the ANC - the former liberation movement of the late Nelson Mandela - to 40% in Wednesday's election, down from 57.5% in the 2019 parliamentary vote.

That means it must now share power, likely with a major political rival, in order to keep it - an unprecedented prospect since the end of white minority rule in 1994.

From the official announcement of results expected on Sunday evening, political parties will have two weeks to work out a deal before a new parliament sits to choose a president, who would likely still emerge from the ANC as the biggest party.

Counting from the May 29 poll was almost complete on Sunday morning, with results in from 99.9% of polling stations.

Before Wednesday, the ANC had won every national election by a landslide since 1994, but over the last decade its support has dwindled as the economy stagnated, unemployment rose and roads and power stations crumbled.

The main opposition party, the Democratic Alliance (DA), had 21.8% of votes in last week's election. uMkhonto we Sizwe (MK), a new party led by former President Jacob Zuma, managed to take 14.6%, doing most of the damage to the ANC.

The far-left Economic Freedom Fighters (EFF), led by former ANC youth leader Julius Malema, got 9.5%.

Both the DA and the small Inkatha Freedom Party said their leadership would meet separately on Sunday to discuss their next steps.

"The DA is awaiting the final results. Once those are certified, we will look at the final lie of the land, and the structures of the party are meeting to determine the next way to proceed," said DA spokesperson Charity McCord.

There were, however, no coalition talks yet underway with any party, she added.

Despite doing better than almost anyone expected, MK said it was considering challenging the results in court.

(Writing by Joe Bavier; Editing by Emelia Sithole-Matarise)