Cosatu says life has become unaffordable
Thousands of South African trade unionists have taken to the streets to protest against rising food prices.
The march, organised by the Congress of South African Trade Unions (Cosatu), took place in Johannesburg.
Cosatu's leader Sdumo Dlamini said the protest would send out a message that the cost of living was too high.
"An ordinary person canít afford to survive anymore," he said. People were also demonstrating about the rising prices of electricity and fuel.
"Basic food has got to be affordable to anyone, in particular the poor and unemployed workers," Mr Dlamini said.
About 5,000 people attended the march, which started in the city centre and continued to the offices of the energy company Eskom and one of the main supermarkets, Pick ín Pay.
The demonstrators handed over petitions to both organisations asking them to stop increasing their prices.
A spokesman for Pick 'n Pay said they were taking the issue of rising costs very seriously and would consult their suppliers.
Cosatu accuses the major food retailers of profiting from the rising food prices.
Cosatu spokesman Patrick Craven said: "We want to put an end to price-fixing, particularly attempts to make extra profit under the cover of the global increase in prices."
Eskom is already in talks to increase its prices by up to 53%, following a spate of severe power cuts.
Food price inflation in South Africa is now at around 14%.
The cost of basic foods has risen sharply around the world in recent months, sparking protests in countries from Haiti to Indonesia.
Rice prices on world markets have climbed about 75% in just two months, and the cost of wheat has rocketed by 120% in the past year.
The price of maize, an African staple, has more than doubled since the beginning of 2006.
Reasons for the increase in food prices include a growth in the world's population, which is expected to top nine billion by the middle of the century, and the emerging economies such as China and India, whose middle classes are now consuming more.
The president of the World Bank, Robert Zoellick, has called for immediate action.
After a meeting with the International Monetary Fund at the weekend, Mr Zoellick called on governments to provide the United Nations World Food Programme with $500m in emergency aid by next month.