The ANC's national executive committee raised concerns over leakages of confidential information from its meetings, secretary-general Gwede Mantashe says.
"This tendency was strongly criticised as it reduced national leaders of the ANC to being sources of journalists," he told reporters in Johannesburg during a post NEC briefing.
"You become faceless... it's damning."
Mantashe said the African National Congress needed to "understand" who these sources were and do everything it could to "discourage this tendency".
The ANC held its four-day NEC meeting in Mangaung (Bloemfontein) at the weekend. It was its last NEC meeting for the year.
Mantashe said the meeting focused on the centenary celebrations next year, completing organisational issues and considering the presentation for the ANC's national policy conference.
The ruling party's national policy conference will take place from June 26 to 28 next year at Gallagher Estate in Midrand.
"The plans are firmly underway," he said.
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