African Union Commission chairperson Nkosazana Dlamini Zuma said on Monday her prolonged stay in Addis Ababa would not affect her possible campaign for the African National Congress (ANC) presidency.

She was due to finish her term in Addis Ababa in October, but AU leaders meeting at their summit in Kigali, Rwanda, were unable to agree on a replacement on Monday. So they asked her to stay on until January when new elections would be held at the next AU summit in Addis Ababa for the chair and all the other members of the AU Commission.

"Of course my term should have ended in October, but the way I look at it is that I’d come to serve the continent and if the continent has challenges, and they want me to stay an additional six months, I should do it, and do it with pleasure," she told journalists after the summit ended.

On the possible impact of her delayed return to South Africa on the presidential bid she is widely speculated to be planning, she said: "No this has got nothing to do with the ANC. The ANC has its own processes.

"And in any case, the conference is 2017 December," she added, laughing.

Earlier the AU leaders held an election for a new AU Commission chairperson to replace her, but none of the three candidates won the two-third majority required by AU rules, said outgoing AU chairperson Idriss Deby, President of Chad.

The three candidates were Botswana’s foreign affairs minister Pelonomi Venson-Moitoi, representing southern Africa, Equatorial Guinean foreign minister, Agapito Mba Mokuy representing central Africa and former Ugandan vice president Specioza Naigaga Wandira Kazibwe representing east Africa.

Official sources said Kazibwe was eliminated in the first round and the other two candidates went into a second round. But neither could muster two thirds, as 20 to 30 of the AU leaders abstained.

The sources said the AU would look for better candidates before January.

Weeks ago, officials were saying former Tanzanian President Jakaya Kikwete would be approached to run, but it is not clear if he was in the end approached and whether he agreed. Abdoulaye Bathily, a former Senegalese minister and diplomat, has also thrown his hat into the ring, according to news reports.

South African officials have also mentioned Algerian foreign minister Ramtane Lamamra as a possible candidate. He had been expected to run against Dlamini Zuma at the Kigali summit if she decided to go for a second term, which she eventually did not. It is not quite clear why Lamamra did not put his name forward, although his candidature did face potential technical problems. One was that he has already served two terms as AU peace and security commissioner and the AU’s two-term limits might have barred him from standing for a third term as chairperson.

The other reason speculated on for him standing back was that no country may have more than one commissioner at one time and Lamamra’s compatriot Smail Chergui had been nominated for a second term as peace and security commissioner.

But South African officials had said that if the elections for the AU chair were postponed until next January, Lamamra might be persuaded to contest them.