Agriculture Minister Tina Joemat-Pettersson came under fire on Friday for her refusal to address the Cape Town Press Club in the presence of a DA shadow minister.
Her conduct was unacceptable, said two press clubs and the Democratic Alliance MP concerned, Pieter Van Dalen.
"If minister Joemat-Pettersson can't take the heat, she needs get out of the kitchen," said Van Dalen.
Cape Town Press Club chairman Donwald Pressly said: "One is surprised that an elected politician and servant of the entire electorate is unable to take the heat of probing questions from whatever quarter."
National Press Club chairman Yusuf Abramjee said the minister's conduct "smacks of arrogance and this nonsense must stop".
Joemat-Pettersson was invited to address a meeting of the Cape Town Press Club on Friday. She refused to speak until Van Dalen, a member of the club, left.
Van Dalen said he had been looking forward to hearing her speech as she did not often engage with the media or public.
"But when Minister Joemat-Pettersson realised I was there, she refused to continue with her address unless I left the premises."
He agreed to do so because he did not want to deny the audience the opportunity of hearing her speak, he said.
"The minister's conduct at this morning's event was unacceptable," said Van Dalen.
"It indicates a disregard for basic principles on which our democracy is based, such as accountable and responsive governance."
Joemat-Pettersson had allowed her personal sentiments to affect her ability to do her job, he said.
On Thursday, he called on Joemat-Pettersson to resign during the debate on her department's budget vote due to "her questionable performance over the last three years and the poor state of her department".
Van Dalen said her conduct at the Press Club was "irrational".
"I am even more resolute in my belief that the minister is unfit to hold public office".
Pressly said Joemat-Pettersson's office had accused the club of dishonesty over its guest list to the breakfast meeting.
"Van Dalen is a fully paid-up member of the Cape Town Press Club, and as such is entitled to attend any Cape Town Press Club event he chooses to attend," he said in a statement.
Joemat-Pettersson's spokesman, Rams Mabote, said he could not understand why the club took exception to the minister's reaction.
"The minister goes to Parliament... she addresses politicians every day, so why is she expected to at the Press Club? Why don't they invite other political parties, then?"
He said Joemat-Pettersson's office did not know her shadow minister would be at the event, contending this was not the appropriate setting for political debate.
Pressly said the minister's office had "no prerogative" to dictate to the club which of its members were allowed to attend its own meetings.
"Perhaps it is a case of the answers being potentially embarrassing, rather than the questions," he said.
Abramjee said he would not have allowed Joemat-Pettersson to address the meeting if she was not prepared to speak in front of Van Dalen.
He said it was "disrespectful" of her to use the public platform provided by the Cape Town Press club for "petty politicking".