Political tensions and weak economic growth in South Africa are the biggest challenge to its sovereign credit rating, Moody’s said on Wednesday.

“Political tensions impeded key structural reforms such as comprehensive reforms of state-owned enterprises which are yet to take place and hampered growth, another key credit challenge,” said Moody’s, which rates South Africa two notches above junk status with a negative outlook.

S&P also said last week that infighting in the ruling African National Congress could derail government efforts to improve policy implementation and that Pretoria had little room to increase spending.