ANC treasurer-general Paul Mashatile says President Jacob Zuma must step down, to avoid creating two centres of power in the country.
"Our view is that there should be a change of guard," Mashatile told CNBC Africa's Political Capital on Friday.
"You need to transfer power, you can't have two centres of power. We want to see a situation where there is one centre with no tension and the best possible way is if the state president exits," he said.
Mashatile's comments come as the ANC top six, led by party president Cyril Ramaposa, are due to meet with Zuma this weekend to ask him to resign.
Mashatile gave the strongest indication yet that the leadership is under pressure, following the National Working Committee [NWC] meeting earlier this week.
News24 reported earlier this week that members of the NWC demanded the top six "confront" Zuma, while others insisted that he should step down before the State of the Nation Address due on Thursday.
A source said the NWC demanded that the Top 6 report back to them on the outcome of their engagement with Zuma.
There was also a call for an emergency National Executive Committee meeting, should Zuma dig his heels in and refuse to step down.
In the interview, Mashatile said they had promised the NWC feedback on the matter.
He added that the best way to handle it was to engage with Zuma in order to show him they were not "booting him out".
Zuma's job has been on the line since the December elective conference that saw Ramaphosa beating rival Dr Nkosazana Dlamini-Zuma and being named as the party's new leader. However, Zuma still has support within the top 6 with Secretary General Ace Magashule and his deputy Jessie Duarte defending his continued stay at Union Buildings.
Ramaphosa, Mashatile, chairperson Gwede Mantashe and deputy president David Mabuza want him to step down.
However, some senior members have pushed for him to go in order to "avoid two centres" of power with Zuma as head of state and Ramaphosa as party president. They also fear his continued stay could cost the party in the upcoming 2019 general elections.
Mashatile told the broadcaster that the party's leadership wanted Zuma's exit to be handled internally. This was to avoid him facing a motion of no confidence in Parliament, brought forward by the Economic Freedom Fighters, on February 22 as well as possible impeachment, the rules of which are set to be finalised before the joint rules committee's last house sitting for the term on March 15.
"We want to avoid that, that is why we want to engage him," he said.Mashatile would not be drawn on what he expected the outcome of the meeting to be.
"All I can say is that the president has agreed to see us."
Zuma's fate has divided the party - with two marches planned for Luthuli house on Monday. One being led by various organisations, including Black First Land First, want Zuma to continue as head of state. Another group of ANC members want to defend the elected leadership.