A coalition of 11 South African opposition parties that aims to topple the African National Congress in next month’s election risks unravelling after its two biggest members suggested they may co-govern with the ruling party if there isn’t an outright winner.

ActionSA, a member of the Multi-Party Charter (MPC), said an ultimatum will be put to the Democratic Alliance and the Inkatha Freedom Party to publicly walk back on their comments that they would consider a tie-up with the ANC in the event that the bloc is unable to form a government, and if they fail to do so they should exit its ranks.

The actions of the DA, the main opposition, and the IFP, the fourth-largest party, were “alarming,” Michael Beaumont, ActionSA’s national chair, said in an interview in Bloomberg’s Johannesburg office on Friday. The MPC “was never set up to be a collective bargaining chip with the ANC, to give you safety and numbers for your preconceived plans. This thing was meant to be an alternative. If that’s where you are heading, you do so without us,” he said.

A series of opinion polls show the ANC will win less the 50% of the May 29 vote for the first time since it took power in the country’s first multiracial election three decades ago. The MPC’s members, who are competing in the election under their own banners, are collectively expected to garner less than 40% support.

DA leader John Steenhuisen has said he’d be prepared to work with the ANC to avert a “doomsday” scenario, whereby the leftist Economic Freedom Fighters is drawn into a ruling coalition. IFP leader Velenkosini Hlabisa said his party won’t allow the country to be brought to a standstill if a government can’t be formed within the prescribed 14 days, and that it may be necessary to install a “grand coalition” that includes the ANC.

Founded in 2020 by Herman Mashaba, a businessman and former DA mayor of Johannesburg, ActionSA won 16% of the vote in the city in a local government vote the following year. The party predicts that it will win between 7% and 11% support in its inaugural national contest — way more than any of the opinion polls show.

Assuming it stays together, the MPC plans to agree on a presidential candidate before the elections to fast-track the process of negotiations to form a government, according to Beaumont.

The bloc plans to conduct lifestyle audits for its leaders who could potentially fill the role and then run a poll to determine who is considered by South Africans to be the most trustworthy and capable of running a government, with Hlabisa and Mashaba considered to be among the strongest candidates, he said.