Three dissidents who resigned their Cape Town city council ward seats this week will contest by-elections under the banner of the new party.

The announcement was made at a media briefing on Tuesday afternoon, where the names of members of an interim steering committee for the party in the Western Cape were also made public.

Former provincial safety MEC Leonard Ramatlakane is to be "convenor" in the run up to the launch of the party on December 16.

Former Cape Town councillor Mbulelo Ncedana is "co-ordinator" and fellow-councillor Ebrahim Sawant treasurer. Representatives of each of six regions of the province will also serve on the committee.

The three Cape Town councillors, plus a proportional representation councillor, resigned after being confronted on Monday by the ANC leadership in the province.

Independent Electoral Commission official Granville Abrahams said on Tuesday night that under the Municipal Systems Act, a municipal manager should proclaim a by-election within 14 days of a vacancy occurring.

If this was not done, the responsibility for the proclamation shifted to the provincial MEC for local government.

Practice in the Western Cape was to simply leave it to the MEC, he said.

Whoever did the proclamation, the by-election had to be held within 90 days of the vacancy, Abrahams said.

This puts the by-elections in early February at latest.

The general election is expected to take place in March or April next year.