"On May 5 2012 we had a regional general council in preparation for the provincial congress," Bheki Ntshangase said.
"We declared that we knew that it wasn't the time for talking about leadership but the conclusion was that when the time comes we will be behind the president."
The ANC has barred its members from openly declaring their support for candidates until nominations opened in October.
Ntshangase said the entire region, which is the ANC's biggest, was in agreement that it would back Zuma for a second term as party president.
The region's branches had been instructed to assess the ANC's current leadership, which was elected at its last conference in Polokwane in 2007.
Ntshangase said the region was happy with the progress the current national executive committee and Zuma had made in the last four years.
He said it was the first time all provinces were focusing on a presidential infrastructure commission. Another achievement was the process of implementing the national health insurance and the National Planning Commission.
"We are just giving our evaluation. We are still fully behind the leadership elected in Polokwane," said Ntshangase.
The eThekwini region has over 100 branches and more than 66 000 members.
The region was expected to send a strong delegation to the ANC's national elective conference in Mangaung in December.
Ntshangase said branches within the region would start meeting on September 1 to discuss their nominations for leaders.
"All the branches will call general meetings … So on the final day [in October] we are ready," he said. – Sapa