The majority of the City of Cape Town council's 32 New National Party (NNP) councillors have signed papers saying they have left their party and intend joining the ANC during the two-week floor crossing period which starts at midnight tonight.
This means the ANC will make up the majority of the council.
The prescribed Independent Electoral Commission (IEC) papers have to be handed to the IEC chief electoral officer, Pansy Tlakula, before September 15 when the walkover period ends.
The NNP started celebrating early with a karaoke event on Monday afternoon where they sang "songs of new beginnings".
NNP caucus leader in the council and deputy mayor Gawa Samuels belted out Tom Jones's It's not unusual.
Meanwhile, the Democratic Alliance (DA) and the Independent Democrats (ID) said they are still hoping to get their share of defectors. In addition, the ANC said a few DA councillors had expressed interest in joining the party.
According to the floor-crossing rules, 10 percent or more party members must leave a political party to constitute a walkover. If less than 10 percent of members want to leave a party to join another party, they will be prohibited from doing so.
IEC provincial head, Courtney Sampson, said: "The members must prove that the party to which they are crossing has accepted them. If they join another party, they keep their seats. But if they are not accepted by the other party, they lose their seats. They can only move once. They cannot go back (to the original party)."
Samuels said the majority of NNP councillors will join the ANC tomorrow. They will retain their posts within the council until the next local government elections.
The ANC's existing 81 councillors need at least 20 NNP members to join them in order to have the majority in the council.
Said Samuels: "More than 20 NNP councillors have signed to join the ANC.
"If the DA thinks they are taking over the council, they are living in a dream world. Two or three NNP councillors will stay on as NNP members and have dual status."
ANC chairperson in the council, Saleem Mowzer said: "The majority of NNP members have committed themselves and will be walking over to the ANC to ensure that the ANC has the majority in council.
"We have been talking to a number of councillors from other political parties, including the DA. But it is their decision.
"Discussions with councillors from other political parties will continue until September 15."
The DA leader in the council, Kent Morkel, downplayed the walkover on Monday.
"The outcome of the crossover is of limited importance. What matters in a democracy is how voters express themselves at the ballot box," he said. "The previous walkover and the NNP's dismal performance in the last election have shown that the behaviour of the politicians during this period had no relevance to the thinking of the electorate."
Asked about speculation that a few DA councillors wanted to join the ANC, Morkel said: "Nobody is leaving the DA."
ID general secretary Avril Harding said he had spoken to a number of interested councillors from the African Christian Democratic Party, DA and NNP at the City of Cape Town and other Western Cape municipalities.
The ID sent out about 7 000 smss to councillors across the country, urging them to join the party and were expecting about 30 councillors to walk over to the party nationwide