A spokesman for a mineworkers' union in South Africa says gold miners will go on strike next week after talks with South Africa's Chamber of Mines collapsed Friday.

Lesiba Seshoka, a spokesman for the National Union of Mineworkers, said Friday that the strike will start Tuesday after the Chamber of Mines — which represents mine owners — did not improve its last offer of a 6 percent pay raise. The union, which represents about 64 percent of South Africa's 120,000 gold miners, seeks a 60 percent raise for its members.

The strike will affect the country's top gold producers, including AngloGold Ashanti and Gold Fields.

The looming strike threatens to escalate South Africa's labor unrest, with thousands of workers in aviation, construction and auto sectors already striking over wages.