The African National Congress (ANC) will give an early indication on Wednesday of its response to last week's election, which ended its 30-year run as the majority party and plunged South Africa into political uncertainty unseen in the democratic era.

The ANC, which is still the largest party but can no longer govern alone, said it would hold a news conference at 12pm, but it is not expected to make an announcement about any coalition plans as it has yet to decide on its position.

Voters, politicians and financial markets are on tenterhooks to find out which party or parties the ANC will approach to form a national government and will be scrutinising every detail that comes out of the news conference for clues on what to expect.

The ANC's choice will steer the nation in one of several very different possible directions as contender parties range from the free-marketeer Democratic Alliance (DA) to the Marxist Economic Freedom Fighters (EFF), with a range of smaller parties with their own specific identities also in the mix.

A note to media said the news conference would include an announcement about a National Executive Committee (NEC) meeting "to be held this week", suggesting that the meeting had been postponed from Wednesday, when it had originally been scheduled.

The NEC meeting will be the forum where the party's most senior figures attempt to thrash out a consensus on which parties to work with and what kind of a deal to offer them.

An ANC official said "an organised corner" within the party was expected to push for a deal with the EFF and uMkhonto we Sizwe (MK), a party led by former president Jacob Zuma, but they were outnumbered by those favouring an arrangement with the DA.

"The centre and probably the majority of the ANC internally in the NEC see the value of the DA deal because it gives us a cabinet and a lot of power, so they are likely to do that," said the official, who is not an NEC member but is familiar with discussions at the most senior level.

The official, who is a supporter of party leader President Cyril Ramaphosa, said he was all but certain to remain in post even if some NEC members broke ranks and called for his resignation.

The ANC's options for a national government include a formal coalition or a confidence-and-supply deal whereby one or more parties agree to support it on key votes like the budget, in return for a role in some policy and legislative work.

An ANC spokesperson responded to a request for comment on whether the NEC meeting had been postponed by resending the note on the news conference.

The ANC official, who did not wish to be named, said it was unlikely the NEC would swiftly resolve the issue of national government.

"It is more likely the NEC will beef up the negotiating team and give them a mandate to look into one or two options and to say if there is a preference this way or that way, because if you are negotiating you don't come out and put all your cards on the table," the source said.

The news conference will also be about the outcome of Tuesday's discussions by an internal working group and about the selection process for ANC candidates to be provincial premiers, according to the note to media.