It was worrying that President Jacob Zuma was booed by members of his party’s alliance partner the Congress of South African Trade Unions (Cosatu), Umkhonto we Sizwe (MK) Military Veterans Association chairperson Kebby Maphatsoe said on Wednesday.

“As a leader you must expect to be booed. It’s not a new thing, but it is wrong when it’s planned by your own alliance comrades,” he said on the sidelines of discussion about housing for MK military veterans.

“If it was opposition parties then we don’t have a problem, but when other members of the alliance sing the same tune as our enemies it’s a problem. We will doubt their understanding of the national democratic revolution,” he said.

Members of Cosatu-affiliated unions booed and heckled Zuma at the labour federation’s annual Worker’s Day event in Bloemfontein on Monday.

They refused to let him speak. At least three unions had written to Cosatu questioning why it was allowing him to speak on behalf of the African National Congress (ANC). Cosatu and the South African Communist Party had called for Zuma to step down as the country’s president following his large-scale Cabinet reshuffle on March 31.

Unions felt Zuma’s appearance at the national gathering would send confusing messages. Cosatu claimed it sent an invitation to the ANC and had no say over who it sent to the event.

Cosatu leader Sdumo Dlamini was also booed and shown the “change” sign when he greeted the crowd at Monday’s rally. Dlamini had been accused of being a Zuma sympathiser.

Maphatsoe said Zuma had been booed in public before - during former president Nelson Mandela’s memorial service in 2013.

“Cosatu must go back to the drawing board and concentrate on the plight of the working class as much as we are concentrating on the plight of the military veterans,” he said.

It could not get involved in the ANC’s factional battles. Maphatsoe said ANC leaders needed to speak with one voice or keep quiet.

“When leadership of ANC speaks in forked tongues and different messages it doesn’t bring unity in the ANC.

“We know for a fact that these things have been planned long ago. It’s the build-up of regime change. What worries us more is when our own comrades are beginning to sing the tune of opposition parties.”