Higher education minister Blade Nzimande withheld for three years a report that found free university education was viable, the Mail & Guardian reported on Friday.
Nzimande received the study in December 2012 from a working group he appointed in 2010.
The group, chaired by Nelson Mandela Metropolitan University vice-chancellor Derrick Swartz, investigated the best model for free tertiary education.
It proposed that the system would be similar to the National Student Financial Aid Scheme (NSFAS), where applicants would have to prove they could not afford fees.
Salim Vally, a University of Johannesburg associate professor who was in the working group, told the newspaper he did not know why the report was not released to the public.
Department of higher education spokesman Khaye Nkwanyana reportedly said Nzimande sent the report to the treasury in 2012 to find out if they could fund the model.
Nkwanyana said treasury concluded it would be costly and would compromise on things like social grants.
He said the best option was to continue expanding NSFAS and that he could release the report at any time, when given the go-ahead, so that criticisms could be addressed.
The treasury said government had drastically increased funding to NFSAS.
On Friday, thousands of protesting students will descend on the Union Buildings in Pretoria to confront President Jacob Zuma.
They will wait for the president’s comments on the tuition fee hike debate that has gripped the country since last Wednesday.
The protest started when Wits University students protested against a proposed 10,5% fee hike. It then spread to campuses nationwide.
Police had used stun grenades to disperse large groups of protesters, most notably on Wednesday when students stormed the parliamentary precinct while finance minister Nhlanhla Nene was delivering his mid-term budget. — News24