South Africa's ruling ANC party said Saturday that it "must act decisively" to rebuild its reputation, as local media reported that President Jacob Zuma could soon be forced to leave office.

Zuma has been under growing pressure to resign since he was replaced as head of the African National Congress (ANC) in December by his deputy Cyril Ramaphosa.

Zuma's presidency has been engulfed by corruption scandals and a weakening economy, with the party losing public support ahead of next year's general election.

Ramaphosa's supporters are keen for him to take over as president and try to revive the economy before the election, when the ANC could lose its grip on power for the first time since the end of apartheid.

"The ANC must act decisively and with determination to rebuild the bond of trust between our people and the movement," the party said in a statement after a two-day meeting of its senior members.

The statement addressed criticism that South Africa currently has two centres of power -- Zuma still in office as president, while Ramaphosa heads the ruling ANC party.

"(Party) officials, led by President Ramaphosa, will continue their engagement with President Jacob Zuma to ensure effective coordination between the ANC and government," it said.

- Zuma to leave, but when? -

The News 24 website said the party's executive meeting had decided that Zuma must leave office, but that no exact timeline had been agreed.

"We will have a new president in the coming weeks," it quoted one unnamed party member at the meeting as predicting.

Zuma's closest allies still hold senior positions in the party, and he could in theory remain president until the 2019 election that marks the end of his second and final term in office.

His control over the ANC was shaken when his chosen successor -- his former wife Nkosazana Dlamini-Zuma -- lost out to Ramaphosa in the closely-fought race to be party leader.

Zuma, 75, could leave office either by resigning, through losing a motion of no-confidence in parliament or impeachment proceedings.

He could also be recalled by the ANC, forcing him to step down.

Whoever is president on February 8 will deliver the annual state of the nation address in parliament -- providing one deadline for political manoeuvering.

Ramaphosa, 65, is a former trade unionist who led talks to end white-minority rule in the early 1990s and then became a multi-millionaire businessman before returning to politics.

The ANC, which has ruled since 1994 when Nelson Mandela won the first multi-racial election, recorded its worst-ever results in 2016 local polls.