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JOHANNESBURG, Oct 8 (Reuters) - South Africa's union of local government workers has filed notice to embark on a national strike, a spokesman said on Monday, a sign that crippling labour unrest in Africa's top economy is widening into the public sector.
"The union is mobilising towards a national protest, which would begin as soon as this week," Tahir Sema, a spokesman for the South African Municipal Workers Union told Reuters.
The action, which could lead to a one-day protest or an indefinite strike, would call for medium and lower-income workers to receive market-related salaries and for pay parity among workers across South Africa's provinces, Sema said.
Close to 100,000 workers, including 75,000 in the mining sector alone, have taken to the streets in recent weeks in often violent protests, demanding higher wages and better income equality in Africa's biggest economy.
The wildcat strikes have shut down great parts of the mining industry in the world's top producer of platinum and a major supplier of gold, pushing prices of precious metals higher.
SAMWU has more than 190,000 members country-wide and a majority was expected to participate, Sema said.
Workers were calling for medium and lower-income workers to receive market-related salaries and for greater pay parity among workers across the provinces, he added.
The strikes pushed the rand to a fresh 3-1/2 year low on Monday and prompted Moody's last month to cut South Africa's government bond rating, citing the government's difficulty in keeping up with economic challenges and widening strikes.
Anglo American Platinum fired 12,000 wildcat strikers on Friday, a high-stakes attempt by the world's biggest platinum producer to push back at a wave of illegal stoppages sweeping through the country's mining sector and beyond.
Kumba Iron Ore said it was losing 120,000 tonnes of finished product per day due to an illegal strike at its Sishen mine in South Africa and it would be able to continue supply customers from stockpiles only until mid-October.
Strikes have spread beyond the mining sector, with Shell saying on Friday it would not be able to honour contracts to deliver fuel near Johannesburg because of a trucking strike.
(Reporting by Agnieszka Flak; editing by David Dolan)
Keywords: SAFRICA STRIKES/MUNICIPAL