The Democratic Alliance (DA) said on Thursday it would push for a scheduled motion of no confidence in President Jacob Zuma to be brought forward should the ruling African National Congress (ANC) fail to have negotiated him out of power by Sunday.

"It cannot carry on indefinitely. I think Sunday is a reasonable time for them to have resolved their own internal issues," DA chief whip John Steenhuisen said.

He was referring to one-on-one negotiations between Zuma and Deputy President Cyril Ramaphosa, who replaced him as ANC leader in December and is now positioned to succeed him as leader of the country and the party.

The ANC on Sunday asked Zuma to step down after more than eight scandal-plagued years in office.

Steenhuisen said the longer the talks dragged on, the more Ramaphosa risked appearing weak.

"Every hour that passes shows Mr Zuma is still in the driving seat."

Steenhuisen said uncertainty was bad for the country and disruptive for the business of Parliament, where the Speaker this week took the extraordinary step of postponing the president's annual state of the nation address to allow the ANC to settle its leadership battle,

Speaker Baleka Mbete last week scheduled a debate on a motion of no confidence in Zuma tabled by the Economic Freedom Fighters (EFF), the country's second largest opposition party, for February 22.

"If the ANC cannot resolve this by Sunday, we must bring the EFF motion forward and vote him out," Steenhuisen said.

He argued that the matter needed to be resolved so that Ramaphosa could be elected by the National Assembly and deliver the state of the nation address, ahead of the tabling of the 2018 national budget which is set for February 21.