Johannesburg: The family of four Indian-origin South African siblings detained in Saudi Arabia for the past month without charge has appealed to President Jacob Zuma to intervene to secure their release.

According to Nazir Desai, Saudi authorities have declined to say why his sons Waliullah and Wasiullah, both lecturers in Arabic studies, and their sisters Huddah and Thembi, both students in Saudi Arabia, have been in custody for more than a month without being charged.