Humphrey Mmemezi, an executive of the ruling African National Congress, last year ran up a 10,000-rand (US$1,220) bill on the credit card at a McDonald’s restaurant in Pretoria.
But the funds made their way out of the McDonald’s account, into another account and finally to a Johannesburg art gallery.
“After consultation with my organisation, through the ANC integrity committee, … I have decided that the most honourable thing to do under these circumstances is to step down,” as regional minister for Gauteng province, he said in a statement.
The opposition had tried in vain to get the former anti-apartheid activist to explain the transaction.
He has now admitted to also using the card to buy suits in India and groceries from a local store, but said he had reimbursed for that and the artwork, blaming his use of the card for personal use on “ambiguity” in instructions contained in the ministerial handbook.
“These purchases were an error of judgement on my part for which I take full responsibility and would want to apologise profusely,” he said.
Mmemezi, 57, had served in the Gauteng provincial government for 18 months.
McDonald’s operations in South Africa are owned by Cyril Ramaphosa, the former trade unionist who took part in the negotiations that saw the end of apartheid and is now a top businessman.
The fast food giant said in May the owner-operator “was empathetic to the needs of a friend, the artist” by offering him to use his restaurant’s credit card facility to process the transaction.
The artist did not have facilities to receive card payments.
“In hindsight, the owner-operator agrees that this was an innocent error of judgment,” McDonald’s said.