Zille was responding to critics following an announcement that she has joined the Institute of Race Relations as a senior research fellow.
“I have been a committed exponent of non-racialism my whole life and have lived that value every day. Now non-racialism is seen to be 'conservative' which is nonsense. It is racial nationalism and identity politics that are retrogressive,” she said.
In its announcement on Sunday, the Institute said joining forces with Zille would bring together two of the loudest reformist voices in the country.
Meanwhile, Zille, who served as the DA leader between 2007 and 2015, cited her reason for joining the IRR as being because the organisation “espouses liberal values and is trying to build the moderate, non-racial middle of South African politics”.