South Africa’s former president, Jacob Zuma, has said his political party – uMkhonto weSizwe (MK) – will join the opposition alliance in parliament.

He said it would co-ordinate resistance to the governing coalition led by the African National Congress (ANC).

Despite this, MK said it maintained that last month’s elections were rigged and wanted the results annulled.

Mr Zuma’s speech on Sunday was read by MK spokesperson Nhlamulo Ndhlela who said the ANC was no longer part of the solution.

Mr Zuma said there was no government of national unity in South Africa and described the partnership as a “white-led unholy alliance between the DA and the ANC of Ramaphosa”.

The ANC lost its outright majority for the first time since the end of apartheid and sealed a power-sharing agreement at the weekend with the Democratic Alliance (DA).

Several smaller parties have also joined what the ANC calls a national unity government. Their MPs on Friday re-elected ANC leader Cyril Ramaphosa for a second term as president.

Mr Zuma also confirmed on Sunday that MK had lodged a court case demanding that the election results be declared invalid and that a new vote be held.

Mr Zuma told his supporters to “submit or fight” back by using peaceful means.

“We will fight to win back our country from the enemies of progress,” he said.

There have been fears that Mr Zuma’s stance would trigger violence among his supporters, who sparked deadly riots in July 2021 when he was jailed for refusing to give evidence at a public inquiry into corruption during his administration.

Police reinforcements have been sent to his home province, KwaZulu-Natal.

The 82-year-old Mr Zuma said his party would soon go to parliament after boycotting Friday’s first sitting.

The newly formed MK did surprisingly well in the elections, becoming the country’s third-largest party and taking a big chunk of votes from the ANC.

It won 12% of the vote and obtained 58 seats in parliament.

Mr Zuma said the MK would become part of the official opposition, joining a group of small parties calling themselves the Progressive Caucus.

Mr Zuma was an ANC veteran but fell out with the party after he was forced to quit as president in 2018 over corruption scandals. He has always denied any wrongdoing.