Cape Town, Jul 17 (IANS): South Africa's renowned anti-apartheid activist and a top leader of the ruling African National Congress (ANC) Jessie Duarte passed away early Sunday morning, her party said in a statement.

Duarte, born on September 19, 1953, was undergoing treatment for cancer and had been on medical leave since November 2021, Xinhua reported quoting the statement.

Duarte, once a personal assistant to South Africa's liberation struggle icons Nelson Mandela and Walter Sisulu, had been serving as Deputy Secretary-General of ANC since 2012, a position in ANC's "Top Six." She was appointed as the acting secretary-general following the suspension of Ace Magashule in May 2021.

"She was both a tower of strength to the organisation as well as a matriarch and pillar of her family," read the statement.

The party said her passing is a "great loss" to her family, the democratic movement and the country as a whole, commending her for dedication to a "united, non-racial, non-sexist, democratic, prosperous and just" South Africa.

ANC also said she is a committed gender activist and consistently committed to advancing the rights of the poor and marginalised.

Duarte will be buried Sunday afternoon in Johannesburg according to Muslim rites.

Various political parties have sent their condolences to her family, including major opposition parties Democratic Alliance and Economic Freedom Fighters.