The ministry of higher education insisted on Wednesday that it bought a R1,1-million seven series BMW for its minister, Blade Nzimande, out of necessity.
Spokeswoman Ranjeni Munusamy said Nzimande, the general secretary of the South African Communist Party, is "opposed to any form of unnecessary extravagance".
"The Minister of Higher Education and Training is a new member of Cabinet in a new department," Munusamy said.
"For the first month following his appointment, the department had hired a seven series BMW for use by the minister. The Department was concerned by the high cost of renting a vehicle and decided that one should instead be purchased in line with the ministerial guidelines."
She said the car was not the property of the minister and was bought for use on official duties within the regulations and in line with the VIP Protection Unit security considerations.
The car was bought from a BMW showroom as a demonstration model at a cost of R1,1-million.
"Minister Nzimande does not condone wasteful expenditure under any circumstances and stands firm in his condemnation of greed, corruption and selfishness in society."
The department was reacting to a statement by the Democratic Alliance, criticising Nzimande for wasteful expenditure.
"It appears that only the very best will do for the leaders of the working class," said a statement from MP Wilmot James.
"In fact, when set alongside his recent comments, Minister Nzimande's purchase of this vehicle gets to the heart of what is wrong with this ANC government and its alliance partners."
The SACP said Nzimande's security had to be taken into account when a vehicle was procured.
"The last risk assessment conducted by the South African Police Service sometime before his appointment as Minister necessitated measures to strengthen and increase his security.
"This included the provision of a car which is able to meet such requirements and respond to the needs of his diary." - Sapa