The strike is over living allowances and planned job cuts

Workers at two Harmony Gold and one Gold Fields mine have walked out in a dispute over pay and planned redundancies.

The National Union of Mineworkers (NUM) said the dispute was being extended because of the behaviour of both firms.

Gold Fields said the strike was illegal and it was going to halt it in court.

The NUM said nearly 30,000 workers at all mines of Gold Fields would walkout at 18:00 local time on Wednesday, which the company confirmed.

Currently 20,000 Harmony staff are out on strike at two facilities in the Free State. The union said this would increase within seven days to cover all Harmony sites, which employ a total of 50,000 people.

'Difficult talks'

In addition to opposing job cuts at the two firms, the union wants monthly living allowances to be raised to 1,200 rand ($189.80; �100) from the current 706 rand.

"Unfortunately, what is clear is that both of these companies are very arrogant," said NUM spokesman Moferefere Lekorotsoana.

"If they think these mineworkers are not human enough to live in decent accommodation, well let them sweat it out."

The two companies, which together account for around half of South African gold production, argue that job losses are necessary, and pay increases are impossible, as their profits are being squeezed by the high value of the rand.

Harmony chief executive Bernard Swanepoel said talks with the NUM had been "difficult" and that he did not think the union wanted a quick resolution.