The ANC criticised Public Protector Thuli Madonsela on Friday for attending a Women's Day event organised by the Democratic Alliance.

"Madonsela's decision to attend a political party rally was ill-considered as it opens up her office to perceptions of political bias," said ANC Chief Whip Mathole Motshekga in a statement.

Madonsela appeared and spoke on Thursday at the event, which was organised by the DA's women's wing, the DA Women's Network.

Motshekga said the Public Protector "rubbed shoulders" with DA leaders at the event.

He argued that Madonsela was jeopardising her constitutional role of independence and impartiality.

"Attending and giving keynote addresses at political events of political parties has the potential to compromise these basic constitutional principles," Motshekga said.

"Members of the public will be justified to ask how she will in future treat complaints against the administrations under the DA."

Motshekga said Madonsela should participate in public outreach such as Women's Day events but should seek an "impartial platform" to do so.

Madonsela's office could not immediately be reached for comment.