Cosatu will support taxi bosses who have threatened to bring Pietermaritzburg to a standstill when ANC president Jacob Zuma appears in court on August 4.
Zet Luzipho, pictured, Cosatu's KwaZulu-Natal secretary, urged employers to take these threats seriously.
"I am just advising them to prepare themselves for the poor turnout at work because there will be no public transport in Pietermaritzburg on that day," Luzipho said.
He was reacting to remarks allegedly made by the chairman of the KwaZulu-Natal Transport Alliance, Eugene Hadebe, at a march to protest against the increasing cost of electricity, food and petrol.
Hadebe said taxi bosses and their drivers, who also want charges against Zuma dropped, were prepared to sacrifice a day's pay for the man expected to become the country's next president.
He assured people who wanted to attend the case that the stayaway by taxi operators would not affect them because their vehicles would be available to transport them to court free of charge.
Luzipho said the taxi bosses' stance sent a clear message that the anger over the injustice meted out to Zuma transcended political allegiance.
"Everybody is concerned about the political bias of the justice system and its political campaign," he said.
"I won't be surprised if traditional healers and other sectors of society also take similar action.
"Our members will come in numbers," Luzipho said.
Previous court appearances by Zuma have been characterised by night vigils.