The protesters from COSATU, the country’s largest union federation and the South African Communist Party are calling for the government to expel the Israeli ambassador in South Africa and to recall Pretoria’s envoy to Tel Aviv.
Both groups are partners in the ANC’s ruling alliance and have prominent ministers in government.
“The vigil is in protest of the recent Israeli attacks on the Gaza Strip,” said an umbrella group calling itself Boycott, Divestment and Sanctions in South Africa.
“A mass protest rally will take place tomorrow outside South Africa’s parliament in Cape Town,” it said.
South Africa’s Business Day newspaper earlier reported the minister of International Relations as saying South Africa would consider recalling its ambassador to Israel at the “appropriate time”.
Minister Maite Nkoana-Mashabane condemned Israel’s “illegal occupation” of Palestinian land and the “extrajudicial killings” of Hamas leaders.
The Israeli air and naval offensive on Gaza which started a week ago has killed 136 Palestinians and five Israelis.