Agang SA says the party is "solid" and that its leader Mamphela Ramphele's decision to become the DA's presidential candidate must still be discussed.
At a media briefing on Wednesday, Agang SA denied there was infighting in the party, saying such rumours were "nonsensical".
"Agang is united, consistent and solid. There is no infighting in Agang," party member Donald Tontsi told reporters in Johannesburg on Wednesday. "To say there is, is nonsensical."
The briefing was held by representatives of all Agang SA's provincial structures. DA leader Helen Zille on Tuesday announced that Ramphele would be the DA's presidential candidate in the upcoming general elections.
Also on Wednesday, Agang SA's Gauteng chair Andries Tlouamma told reporters in Johannesburg that Ramphele cannot make decisions on her own.
"That is going to be our decision, not her decision. We are the custodians of this party ... "There are structures in a party. There are processes to follow to arrive at certain decisions ... This decision affects all of us in the party."
Tlouamma said disagreements were part of politics.
"In a political party, when we disagree, it does not mean we don't like each other ... Even if we have issues to raise with our leader, we will do so without fear," he said. "A political party that takes decisions without robust debate is nothing but a dictatorship."
He said the future of Agang depended on its members.
"There is unhappiness across the country by our members," said Tlouamma. "Our leader has a responsibility to discuss with us the belief she had in the announcement she made."
Tlouamma said Agang SA was giving Ramphele an opportunity to consult with them urgently.
"The consultation was not made. We are still waiting for a consultation with our leader ... We don't believe our leader deserted us. But the decision must come from us."
Tlouamma said it respected Ramphele and appreciated her for founding Agang SA.
"She is a leader of substance, a leader of virtue."
He said the party did not want to use the word "betrayed".
"We don't know where that word came from ... We do not feel betrayed."
Meanwhile, Ramphele accused one of her critics of being part of an Economic Freedom Fighters (EFF) "infiltration" team, SABC radio news reported on Wednesday morning.
She was responding to criticism from Yako Sakhiwo, who was quoted in the New Age as saying Agang SA would elect another leader and still contest the general elections.
The New Age said Sakhiwo was Agang SA's acting Gauteng secretary.
But Ramphele told SABC radio news: "He [Sakhiwo] is not a member of Agang. He has been expelled because he came in as part of an EFF infiltration team and when we found him out we expelled them, including him.
"He is a prohibited person on our premises and the people running our office are going to get him arrested if he were to trespass into our offices ... So I don't know about him carrying any power because he is a persona non grata. He has no standing in the organisation," said Ramphele.
Sakhiwo was quoted as saying in the New Age: "Our leader is taking us where we never wanted to go. If she wants a merger with the DA, she should have consulted us first ... I was with many other fellow leaders and members at our Braamfontein offices and we were all surprised. We even got calls from other party leaders and othe rprovinces who were also surprised."
He said the political party, formed as a "political platform" by Ramphele about a year ago, then launched last June, would still contest the elections with another leader.
Some senior DA members complained to Beeld that they too had to find out about Ramphele's move in the media.
"It is being forced on to us," an MP who was not named told the Afrikaans daily.
Ramphele said the decision not to inform members was "what visionary leadership is", according to the Star newspaper.
"Obviously we haven't consulted the last village, the last township where we have been and are active. But the leadership of Agang in the provinces have been kept abreast."
Ramphele denied she was joining the DA because her own party was going broke, saying "the only party that is bankrupt is the ANC, which is morally bankrupt".
ANC general secretary Gwede Mantashe described the development on Tuesday evening as "rent-a-black, rent-a-leader. We can't be concerned about that". – Sapa