S.Africa's NUM threatens to strike over Kumba lay-offs

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JOHANNESBURG, July 13 (Reuters) - South Africa's National Union of Mineworkers (NUM) said on Monday its members would stop work at Kumba Iron Ore (Other OTC: KIROY - news) if the company went ahead with plans to cut up to 175 jobs, most of them at its Sishen mine.

"The NUM will engage with Kumba Iron Ore management to halt the retrenchments and if the engagements do not work, we will definitely embark on a strike," the union said in a statement.

Kumba, South Africa's biggest producer of the steel-making ingredient, was not immediately available to comment.

NUM said the company had issued a Section 189 last week, a legal requirement that means it will consult with unions, the government and other stakeholders for up to 90 days about the process.

Unions in South Africa's mining industry have become increasingly militant to protest against the persistence of big income disparities and low wages two decades after the end of apartheid.

"The logic of capital requires constant growth in order to accumulate wealth, but this growth is, unfortunately, dependent on exploiting mine workers who still earn poverty wages," the NUM said in its statement.

The tone of South Africa's biggest mining union has also become more strident since long-time general secretary Frans Baleni was replaced last month by David Sipunzi, formerly a regional leader from the gold-producing Free State province.

Kumba, a unit of Anglo American (LSE: AAL.L - news) , has been grappling with depressed prices in the face of slowing demand in China, its largest market.

The company's Sishen mine is in the remote Northern Cape province. (Reporting by Ed Stoddard; Editing by Stella Mapenzauswa and Jane Merriman)