The industrial action in protest of retrenchments at the operation has been ongoing for four weeks, with Gold Fields offering increased severance payments and better portable skills training opportunities for retrenched employees as part of a potential settlement.

It also offered to extend the period over which wages lost by striking employees would be forfeited.

The offer, which was developed in collaboration with the NUM national, regional and branch structures, expired Friday, although the union's South Deep branch decided to continue the strike instead.

Striking workers have lost around R80 million (US$5.9 million) in wages and other earnings since November 2, with the mine losing R6 million per day.

In its September quarter update, Gold Fields had forecast no more output from the mine for the remainder of 2018, downgrading the company's total full-year guidance to 2-2.05 million ounces from the previously planned 2.08-2.10Moz.

"Management has received overwhelming responses from employees not supporting the strike and wanting to return to work. However, they fear the intimidation and threats emanating from the small group of strike leaders," Gold Fields said.

CEO Nick Holland said however long the strike continued, it would not change the restructuring plans, including the 1,082 retrenchments, as these would improve South Deep's long-term sustainability and keep 3,500 people employed. 

"Should the strike continue for an extended period of time though, it could potentially place more jobs at risk. Our immediate focus now needs to be on getting our employees safely back to work and securing their jobs, building our future together and supporting the communities that host us," he said.

The strike has not impacted Gold Fields' share price, which has risen 3.4% in the past month to R40.52 per share.