South Africa's main metalworkers' union said on Monday it had agreed a 12 percent wage increase with the South African unit of steel giant ArcelorMittal .

It is a historic agreement ... to address ... the critical shortage of skilled artisans by ensuring additional improvements on benefits, development and keeping qualified artisans, the National Union of Metalworkers of South Africa (Numsa) said in a statement.

The across-the-board wage increase will come into effect at the end of June.

ArcelorMittal is the world's biggest steel producer. (Reporting by Serena Chaudhry; Editing by Quentin Bryar)

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