Standard & Poor's on Friday, Oct 12, cut South Africa's credit rating one notch to BBB with a negative outlook, saying mining strikes and social tension could reduce fiscal flexibility and hurt growth, Reuters reported.

"We expect underlying social tensions may result in amplified spending pressures and reduce fiscal flexibility for the government," S&P said in a statement.

In particular, the ratings agency said mining strikes could influence political debate ahead of 2014 elections and "may increase uncertainties related to the African National Congress' future policy framework."

S&P's downgrade from BBB-plus takes it one notch below both Moody's Investors Service's Baa1 rating with a negative outlook as well as Fitch Ratings' BBB-plus rating, also with a negative outlook.

"The negative outlook reflects our view that the medium-term political, economic and fiscal ramifications of South Africa's social tensions could deteriorate beyond our current expectations," S&P said.

S&P added that it sees South African growth softening to around 2.5 percent in 2012 and the budget deficit increasing to at least 5.1 percent of output.