Thousands of South African workers downed tools on the day before to protest against a jump in food and fuel prices, closing businesses in two of the country?s biggest provinces.

The walkout in the Western Cape and KwaZulu-Natal provinces, home to two of the nation?s largest cities, was part of a drive by the Congress of South African Trade Unions (COSATU) and its allies to pressure the government to tilt policy to the left in Africa?s biggest economy. They are aiming for a national strike on August 6.

?I don?t even have money to buy bread. I don?t have food in the house,? said Mabel Adams, a factory worker and mother of four who joined 2,000 protesters to march on parliament in Cape Town.

The impact of the mass action was greatest in Durban, where the transport system ground to a halt and many businesses closed as 3,000 protesters, including labour and Communist leaders, marched through the city centre. But major installations appeared unscathed by the walkout.

South Africa?s largest oil efinery SAPREF was operating normally, while the Richards Bay Coal Terminal, the artery for South Africa?s coal exports, was unaffected, officials said.

There were no reports of disruptions at gold, platinum, coal and diamond mines, mostly located in the north of the country. Financial markets also largely ignored the strike with stocks, bonds and the rand all gaining on Wednesday. COSATU said 9,000 people took part in a march in the Western Cape province.

There is rising political tension in South Africa and fear of an economic downturn. Growth has averaged about 5 % in recent years but dropped sharply in the first quarter of 2008.

?Declaration of war?

Business leaders and foreign investors fear labour unrest could combine with an electricity crisis and soaring world oil prices to produce a toxic cocktail for South Africa, a net importer of energy. ?The proposed rolling mass action will affect productivity and drive prices higher. We are looking at millions of rands, if not billions, in lost productivity,? said Neren Rau, chief executive of the South African Chamber of Commerce and Industry.

Unions, instrumental in helping end white minority rule, accuse President Thabo Mbeki of pursuing pro-business policies that have favoured a wealthy elite at the expense of millions of workers and the poor. A sharp increase in the price of petrol and staples such as milk and bread, and a series of interest rate hikes have stoked labour?s determination to thwart the policies.

But writing in the Pretoria News, Finance Minister Trevor Manuel defended government policy, saying it was poor implementation that was at fault in not spreading wealth. ?This poor implementation hobbles our economic and social progress and may in itself prompt a re-examination of policy,? he said, adding inflation targeting, a concern for COSATU, was the best way to tackle price pressures.

?Changing policies piecemeal will do significant damage to the gains that we have already made in creating a sound macro-economic environment.? Unions are also furious over job losses linked to the electricity crisis that began in January. The state-owned power utility Eskom has been rationing electricity to mines and other large industrial customers as well as residents. ?This protest is turning into a declaration of war against the rampant exploitation of the interests of the wealthy over the poor, while the government chooses the side of the wealthy,? said Tony Ehrenreich, COSATU chief in the Western Cape.

COSATU, which has more than 1 million members, and its allies in the small but influential South African Communist Party (SACP) have thrown their support behind Jacob Zuma, the new leader of the ruling African National Congress (ANC) and frontrunner to become the next South African president.