The Sunday Times reported that Cele was drumming up support for an "Anyone but Zuma" camp in the president's home province of KwaZulu-Natal, which was regarded as a Zuma stronghold.
According to the newspaper, Cele had held meetings with Deputy President Kgalema Motlanthe, Arts Minister Paul Mashatile and anti-Zuma groups.
Cele was believed to still have influence in KwaZulu-Natal, where he previously chaired the eThekwini region. As such, he would reportedly be a useful ally to Motlanthe in the province, which has the greatest number of party members.
In Mpumalanga – also previously regarded as loyal to Zuma – Human Settlements Minister Tokyo Sexwale, who is reportedly thought to be interested in standing for the presidency, was expected to attend a "cadre's assembly" with North West Premier Thandi Modise and ANC Youth League deputy president Ronald Lamola on Sunday.
One of the camps opposed to a second term for Zuma met in Sandton on Wednesday and decided to support Motlanthe for president and Sexwale for deputy.
The Sunday Independent reported that Cele attended the meeting, but he denied doing so and said that at the time, he was at his home in Durban, sleeping.
"Unless somebody says I was a Holy ghost, which can be at two places at once," he told the newspaper.
According to the Sunday Independent, Cele, Sexwale and other ANC leaders were identified in an intelligence document as plotting to overthrow Zuma at the Mangaung conference.
The ANC Youth League, which was previously thought to back Sexwale for deputy president, had now reportedly decided to back ANC treasurer Mathews Phosa instead.
The Sunday Tribune reported that the party's provincial and regional chairmen had been warned that turning against Zuma would result in their influence over government tender processes coming to an end.
An unnamed source told the newspaper: "We were told that we would be out in the cold … that we would go hungry".
A pro-Zuma camp, called the "national coalition", was reportedly expected to tell Northern Cape chairperson John Block that if he pledged support for Zuma, corruption charges against him would be withdrawn.
According to the Sunday Tribune, KwaZulu-Natal Premier Zweli Mkhize, Free State Premier Ace Magashule, Mpumalanga Premier David Mabuza and Higher Education Minister Blade Nzimande were rumoured to be members of the national coalition. – Sapa