This is after her protegee, Lindiwe Mazibuko, trounced Athol Trollip to become the DA's number one in parliament and the youngest parliamentary leader of an opposition party.

Addressing journalists following Mazibuko's landslide victory, Zille stood her ground.

"I am a full member of the parliamentary caucus and I would be abdicating my responsibilities if I did not give leadership and if I did not have a close relationship with the leadership of caucus," she said.

Mazibuko, who enlisted the services of a public relations company to boost her public campaign, was flanked by Zille and Trollip as her victory was announced at a press conference in parliament yesterday.

Although Zille refused to disclose the winning margin, The Times has learnt that Mazibuko got 51 votes to Trollip's 30.

On the eve of the elections, senior DA MPs close to Trollip accused Zille of openly campaigning for Mazibuko. The Sunday Times reported of a meeting, at which Zille was allegedly present, in which Trollip was asked to step back and not contest the post. Trollip declined to do so.

Commenting for the first time on the these claims, Zille said as DA leader, she had every right to know and have influence on whatever was taking place in the DA caucus.

"I will continue with the close working relationship with the leader of our parliamentary caucus because that is what I have to do; I am the leader of the DA, I've been elected to give this party direction."

Veteran MP Dene Smuts penned a strongly worded statement that was widely published in the media, in which she detailed her reasons for supporting Trollip in the fierce leadership battle that has thrown divisions within the DA into the open.

But Zille hit back at Smuts, saying the veteran justice spokesman was off the mark in her criticism.

"Internal democracy in the DA is alive and thriving . Dene doth protest too much, - she does her job very well in legislating [but] in this issue she protested too much," Zille said.

Mazibuko is the first black woman to lead the National Assembly's official opposition parties.

She will lead the DA oversight on President Jacob Zuma and his deputy, Kgalema Motlanthe.

Trollip said he would remain as an ordinary MP until his five-year term expires in 2014.