The United States on Thursday criticised South Africa over reports Iranian forces joined naval exercises, warning the decision clouds regional security.
In a statement on X, the US Embassy in Pretoria said Washington viewed the move with concern and alarm.
The embassy alleged South Africa’s defence minister and the SANDF defied a government order regarding Iran’s participation.
Calling Iran a destabilising actor and state sponsor of terror, it said any inclusion undermines maritime security.
The statement also condemned Pretoria for hosting Iranian security forces as Tehran cracked down on protesters.
It said welcoming Iranian units while citizens were shot, jailed, and tortured betrayed freedoms South Africans fought to secure.
Rejecting claims of neutrality, the embassy said solidarity with Tehran meant choosing a regime that represses its people.
The rebuke cast long shadows across southern seas, where diplomacy now collides with the hard tides of power.