Archbishop Emeritus Desmond Tutu has defended former Democratic Alliance (DA) member Patricia de Lille's role as a "unifier in society".

In a brief statement on Wednesday, Tutu said: "Leah and I are very sad that Patricia De Lille's services will be lost to the City of Cape Town. Although she represented a particular political party, she played an important role as a unifier in a society still bearing the scars of its divided past."

The Democratic Alliance confirmed the cessation of De Lille's membership from the party on Tuesday.

James Selfe, chairperson of the DA's federal executive, made the announcement at a media briefing in Cape Town.

The DA charged De Lille with misconduct earlier this year, following various claims.

The embattled mayor survived a motion of no confidence in her in February, but in an internal motion of no confidence against her in April, the party voted to recall her as mayor.

The DA cited clause 3.5.1.2 in its constitution, which says that if a member publicly declares his or her intention to resign, then their membership ceases immediately.

De Lille said she will be challenging the matter in court in a bid to clear her name.