South Africa's Electricity Minister Kgosientsho Ramokgopa has rejected claims that "sabotage" the reason why the country is experiencing its worst outages since November.

On Saturday, the ruling ANC's secretary general, Fikile Mbalula, called it "clear sabotage" and called for "strong extra security measures".

But Mr Ramokgopa said on Sunday that leaks from boiler tubes, which are used in the generation of electricity in power plants, were to blame.

Those leaks caused nine major power units to fail at one, he added.

Two power units are now working again, and the other seven are expected to be up and running within days, according to the authorities.

Major relief is expected when additional power units are added to the grid in March, Mr Ramokgopa said.

South Africa has been experiencing power blackouts - known as load-shedding - for several years. Many people are forced to go up to six hours a day without power.

Thsee intensified power cuts come just days after President Cyril Ramaphosa said the end of load-shedding was "finally within reach".