South Africa's National Union of Mineworkers said Anglo American Platinum (Amplats), the world's largest platinum producer, again raised its wage offer on Friday, trying to head off a strike that could cause a jump in global prices of the precious metal.

The platinum sector is the latest to be affected by a wave of disputes in the country's mid-year strike season after stoppages in other mines, steel and fuel threatened to dent growth in Africa's biggest economy.

There is an improved offer will be taken to members for consideration, NUM spokesman Lesiba Seshoka told Reuters. He expects a vote to start on Monday and would not disclose details of the offer.

The union will meet Amplats again on Aug. 31.

The company on Thursday offered raises of between 7.5 percent and 8 percent, up from a previous offer of 6 percent to 7 percent.

NUM lowered its demand to between 11 percent and 12.5 percent from 15 percent, which is triple the inflation rate.

The union has said its members at Impala Platinum rejected a revised offer from the world's second largest producer of the metal and will refer the dispute to arbitration.

We insist on a double-digit increase across the board, said Eddie Majadibodu, the NUM's chief negotiator at Implats.

Implats had raised its offer to between 8 and 10 percent, while the union has been asking for 14 percent.

NUM workers in the gold and coal sectors have already reached deals for 7 to 10 percent increases, which could serve as benchmarks in the platinum talks.

The labour disputes are likely to unnerve investors already wary about putting money into the country due to steep power tariff hikes and a debate around mining nationalisation.

Implats and Amplats account for two-thirds of global platinum supply and any strike could push prices higher.

Platinum rose to its highest since early May on Friday, up 1.4 percent at $1,861.49 an ounce, partly inspired by a rise in gold, widely seen as a safe-haven for investors.


In a separate dispute, more than 200,000 water, sanitation and refuse workers seeking 18 percent wage increases marched without major incident in Johannesburg on Friday after setting fires and looting vendors at rallies in Cape Town this week.

The NUM, with more than a quarter million members in various sectors, has also threatened a strike at state utility Eskom, which supplies almost all of the country's power, after rejecting a 7 percent pay rise offer.

Any significant pay rises would affect the utility's strained balance sheet and could lead to further steep rises in electricity tariffs.

Further wage hikes will make it more costly to hire the workers needed to bring power by 2014 to the 25 percent of the country's households that still have no access to electricity.

Wage deals over the past years of double to triple the inflation rate have made the country less competitive by driving up the cost of a workforce that is already more expensive and less efficient than those in emerging market peers.

But the ruling African National Congress, which is in an alliance with organised labour, does not want to antagonise a group that has supplied it with millions of votes by pushing workers to accept more modest pay increases.