The African National Congress (ANC) in the Western Cape says it is concerned about the spate of resignations by former Independent Democrats (ID) members from leadership positions in the Democratic Alliance (DA).

The ANC in the province on Tuesday said it was not usual for the ANC to get involved in another party's "squabbles", but said the impact of the DA's "ID cleansing" is affecting local councils.

It said three high profile resignations in the past month, including those of Patricia de Lille as the party's Western Cape leader, caucus chairperson Rodney Lentit and Beaufort West Mayor Djorge Malooi, were a sign that the DA in the province was "disintegrating".

Lentit and Malooi both resigned this week from their government positions, but remain party members. While De Lille resigned from her party position she remains in her post as a Cape Town mayor.

"It is clear to us that the ID and its former leaders have lost their usefulness, now that they have helped the DA to attain 66% of the votes in the City of Cape Town," the ANC said in a statement.

"As the opposition in most of these municipalities, we remain concerned about the impact that these threats of resignations have on the stability of local councils and the effect that the DA's leadership crisis [has] on service delivery in these municipalities."

Resignations 'unrelated'

The ID, which was formed in 2003 by De Lille, merged with the DA in 2010.

The ANC claimed that other former ID members were also considering their positions in the party after acting DA leader Bonginkosi Madikizela's victory this Saturday in its interim elections.

Madikizela told News24 on Tuesday that Lentit and Malooi's resignations were unrelated.

Lentit had resigned to enter a business he had been setting up for a while, and Malooi had resigned for personal reasons, he said.

De Lille, meanwhile, is under investigation by the party's ethics committee, along with close confidant and Cape Town metro chairperson Shaun August, for allegedly leaking party documents to the press.

Madikizela maintained there were no divisions in the party in the province, and that his job now as acting leader was to maintain party unity.