The Organisation Undoing Tax Abuse (OUTA) has confirmed that its executive director and head of its local government programme, Makhosi Khoza, resigned.
In a letter seen by News24, Khoza expressed her "earnest gratitude" to OUTA for the chance to work with the body and her "deepest appreciation" to all its members and the board.
A vocal opponent of former president Jacob Zuma, Khoza resigned from the ANC in 2017 and later formed her own political party, the African Democratic Change, which she also dumped before joining OUTA in 2018.
OUTA's Wayne Duvenage said Khoza had left of her own accord, and there was "nothing untoward" about her departure.
"She is pursuing her academic interests among other areas she said she needs time on and we respect her decision," said Duvenage.
"We will continue to have a good relationship with her and consult with her where necessary because she has been valuable to a local government division," he added.
When contacted for comment, Khoza said she would respond to questions later in the day.
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