The new power cuts, called load shedding in South Africa, could mean up to six hours without service a day, said Eskom CEO Andre de Ruyter in a hastily arranged emergency briefing.

Workers are demanding a 10% wage increase - more than what the power utility, which relies on government bailouts, is willing to offer.

They first downed tools over a week ago, plunging the nation into a power crisis in the middle of winter.

The country's main power supplier has been struggling to provide the service for years due to historic infrastructure and funding problems.

South Africa is currently under stage four of load shedding, but to prevent a catastrophic grid collapse this could be ramped up to stage six on Tuesday afternoon.

The impact of sustained power cuts is already having a devastating impact on the economy and on ordinary people’s lives.