Picture: Timothy Bernard.

Johannesburg - Striking miners are slowly returning to South Africa's platinum belt in anticipation that the country's longest and costliest strike could come to an end and work resume, companies and a union official said on Friday.

Marathon talks to end the crippling five-month stoppage continued on Friday after a shock setback this week when the three major platinum producers accused the Amcu union of introducing extra demands to derail wage talks.

A week ago, the two sides said they had reached a wage deal “in principle” to end the strike.

About 70,000 members of the Association of Mineworkers and Construction Union (Amcu) have been on strike since January at the world's top platinum producers, Anglo American Platinum, Impala Platinum and Lonmin.

Many of them have left the platinum belt around Rustenburg, northwest of Johannesburg, for their home villages, in many cases in the impoverished Eastern Cape province hundreds of kilometres to the south.

“The Impala mine is closed, but we are seeing more activity in the townships around the mines, which has to be a sign that people are coming back into those areas,” Implats spokesman Johan Theron said.

Smaller rival Lonmin is gearing up for work to resume in the next week or two and a marked number of people were coming back to work, company spokeswoman Sue Vey said.

“People are anticipating a return to work. I think we are close to an end,” she said.

Mines minister Ngoako Ramatlhodi, who last week pulled out as the mediator of talks but is still close to the process, told Reuters the strike could end this weekend and that production could resume soon.

“The parties are knocking at the door of an agreement. They are working around the clock,” he said.

Meanwhile an Amcu shop steward at Amplats confirmed that workers were returning to the platinum belt and that a mass meeting was planned for Monday.

The strike dragged South Africa's economy into contraction in the first quarter and has so far cost the companies more than 23 billion rand in lost revenue, according to an online tally run by the three firms. - Reuters