Some South African auto workers could down tools as early as next week to push for higher wages, a union official said on Thursday.

"We could well give them a notice to strike as soon as next Thursday ... our lawyers are working on it," Castro Ngobese, a spokesman for the National Union of Metalworkers of South Africa, told Reuters.

The union's demands include 20 percent wage increase.

Thousands of South Africa's public service workers went on a march on Thursday for higher wages in some of the country's major cities after negotiations with the government became deadlocked, a union official said.

Reuters