The threat of a strike is looming over South Africa's booming car manufacturing industry.

According to Reuters, the country's metalworkers' union said on Tuesday that about 15,000 workers may strike next week if the car makers do not take steps to end a wage dispute.

The National Union of Metalworkers of South Africa (Numsa) was reported to have said in a statement it would issue a 48-hour strike notice for workers at eight car manufacturers on Friday unless management showed a "fresh commitment" to resolving the dispute.

The news agency noted the union did not say which manufacturers would be affected, but DaimlerChrysler, Volkswagen, BMW, General Motors, Nissan, Ford, Toyota and Tata all make cars in South Africa with a total of 39,000 employees. Many vehicles are exported.

The union was reported to have said a facilitator had proposed a 9% wage increase for this year, 8% for next year and 7.5% for 2009 but talks broke down after the chiefs of the manufacturing plants rejected the settlement proposal.

Numsa has now revised its demands to 9.5% for this year, 8.5% for next and 8% for the year after, Reuters noted.