South Africa's President Cyril Ramaphosa on Sunday reimposed restrictions for two weeks to combat a surge in coronavirus cases.
The worst-hit country on the continent "is facing a massive resurgence of infection," the president said in a televised address to the nation.
"Our health facilities are stretched to the limit... ICU beds are in short supply," he said as he placed the country on alert level four, just one level below a full lockdown.
Ramaphosa banned all gatherings, except for funerals where numbers will be capped at 50, and also ordered a ban on the sale of alcohol.
Eateries and restaurants will not be allowed to serve sit-down meals, and will only be allowed to sell food for take-away or delivery.
A nighttime curfew has been lengthened by an hour - starting at 9pm till 4am, while all schools should be shut by Friday.
Authorities say the peak of the third wave - fuelled by the Delta variant first identified in India -- will surpass that of earlier waves as the country struggles to quickly roll out vaccinations.
"We are in the grip of a devastating wave that by all indications seems like it will be worse than those that preceded it," Ramaphosa said.
South Africa now counts 1,928,897 coronavirus cases after recording 15,036 new cases on Sunday, a drop from the previous day when 18,762 new infections were diagnosed.
The Covid-19 death toll stands at 59,900.
Leisure travel in and out of the densely populated province of Gauteng -- encompassing Johannesburg and Pretoria, the nation's economic and industrial heartland -- has been outlawed.
The province which accounts for around 60 percent of national infections, has become the epicentre of the outbreak.
South Africa has vaccinated only around 2.7 million people since February.
Most business will forge ahead operating at full capacity, a move he said was to enable as much economic activity to continue as possible.
The economy of Africa's most industrialised country slumped by seven percent in 2020 compared to the previous year.
Health officials across the world have been alarmed by the rapid spread of the Delta variant.