Yesterday, The Presidency said Zille "misled the public" by claiming in her Human Rights Day speech in Port Elizabeth that Zuma had praised the SA Democratic Teachers' Union in his State of the Nation speech.
On Wednesday, Zille said education in Eastern Cape was being jeopardised by a Sadtu strike.
"The conduct of Sadtu over the past two years is nothing short of a national disgrace," she said.
"It deserves censure from every leader, of every party.
"To see President Zuma so flippantly thank Sadtu in his State of the Nation address was to witness political expediency in its worst form. The president sold out the potential and prospects of every South African learner for a few extra votes in Mangaung."
But presidential spokesman Mac Maharaj said that Zuma had not mentioned Sadtu in his speech.
He quoted Zuma as having said only: "Our call to teachers to be in school, in class, on time, teaching for at least seven hours a day remains pivotal to success. We thank the teacher unions for supporting this campaign."
Zille conceded that Zuma did not single out Sadtu, but said in the context of the Sadtu strike, he thanked unions for playing a part in improving education.
"He even looked sheepish as he said it because he knew he should have been condemning Sadtu but chose not to for expedient reasons," Zille said.
"Not a single person listening to the president failed to get the message. That is why parliament erupted in a chorus of condemnation when he made this statement."
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