U.S. motor company Ford has suspended production at one of its South African plants and Japanese carmaker Toyota plans to follow suit as a manufacturing workers' strike hits suppliers of car components.

The two-week-old strike by 220,000 NUMSA union members, who are seeking 12 to 15 percent annual increases, follows on the heels of a five-month strike in the platinum sector that stunted economic growth and export earnings.

The strike, which has hit the supply of beverage cans made by packaging firm Nampak, has damaged wider investor sentiment in Africa's most advanced economy, which is teetering on the brink of recession after a first-quarter contraction caused in part by the platinum strike.