South Africa's Anglo Platinum , the world's largest producer of the precious metal, has paid an ex-gratia increase to its 46,000 workers to cushion them against inflation, unions said on Monday.

Angloplat had agreed to a wage deal last September that would have seen some of its workers get a 9 percent rise and the rest an 8 percent increase as from July this year.

But it increased their pay by 10.4 percent as a buffer against inflation.

South Africa's CPIX inflation stood at 10.4 percent in April, which prompted the central bank to hike interest rates further, increasing financial pressures on workers.

The country is due to report May CPIX inflation this week.

Angloplat made it clear, however, that it would not open negotiations to change the existing two-year wage deal.

The company said it wanted to alleviate the difficult economic circumstances facing its workers, and that it would have liked to have paid an even bigger amount if productivity improvements had allowed.

The ex-gratia increase received mixed reaction from unions.

The black-dominated and biggest South African mineworkers' union, the National Union of Mineworkers (NUM), said the increase should have been even higher to help workers cope.

If Angloplat was more compassionate, the increase could have been far better than that. It could have brought the increase to workers pay to more than 12 percent given the fact that fuel, electricity and food costs are rising higher, Lesiba Seshoka, NUM's spokesman said.

Reint Dykema, the mining spokesman at Solidarity, a traditionally white trade union welcomed the increase.

We're thankful for this gesture, and it will ensure the long term stability at their operations, he said.

Platinum prices have been strong as traders fretted over the outlook for supply from South Africa.

A South African official last week warned the country could face a severe energy crisis, and state power utility Eskom said it would raise electricity prices.

Angloplat, which produces about 40 percent of the world's platinum supply, was forced to trim its annual output estimate to 2.4 million ounces from 2.47 million ounces in 2007 due to power cuts that have curbed production at South African mines since the start of the year. (Reporting by James Macharia, Editing by Peter Blackburn)

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