African National Congress (ANC) MP Mondli Gungubele is a thorn in the side of Ekurhuleni ANC mayor Mzwandile Masina.

During a regional press briefing in Ekurhuleni on Tuesday, the party's regional executive committee (REC) chaired by Masina called on the party's National Executive Committee (NEC) to institute disciplinary proceedings against Gungubele.

The regional executive questioned Gungubele's standing to chair the Gauteng province's disciplinary committee.

"Here in the region he is quite problematic... He is convening factional meetings. He is funding people and all sorts of things that we think aren’t ANC," Masina said about his predecessor.

Masina took over Gungubele's position as the mayor of Ekurhuleni in the 2016 local elections.

Gungubele is known in ANC circles as a supporter of deputy president Cyril Ramaphosa, while Masina has thrown his support behind Nkosazana Dlamini-Zuma.

Statements by the region’s REC come shortly after the ANC's National Working Committee (NWC) resolved to discipline those who spoke out against President Jacob Zuma in the days leading to the historic motion of no confidence vote.

"His public outbursts on voting [with] his conscience represents the worst form of betrayal of the value system of the ANC," REC deputy chair Robert Mashego said.

Mashego said the REC was shocked and in disbelief over Gungubele's conduct and reiterated that the NEC should "deal" with his conduct.

Responding, Gungubele told News24: "I will not honour that with any response. Those guys have a huge municipality to run."

At least three MPs are said to be in the firing line after the motion of no confidence.

It is estimated that between 30 and 40 ANC MPs supported the motion.

It is understood that members of the NWC labelled it "a plot to remove the ANC from power" and supported Zuma's calls for those members to face a disciplinary inquiry.

Chair of the disciplinary committee, former tourism minister Derek Hanekom, was the first to receive a formal letter from ANC secretary general Gwede Mantashe asking him to give reasons why he should not be removed as chair. He was given 10 days to respond to the request.

Hanekom and three other MPs, Pravin Gordhan, Makhosi Khoza and Gungubele, openly said they would vote with their conscience.

Gungubele said he no longer had confidence in Zuma. His utterances have also been condemned by ANC parliamentary chief whip Jackson Mthembu, who labelled him as defiant.