President Kiir fired the minister of finance and economic planning, Athian Ding Athian, and Interior Minister, Paul Mayom Akec.
The two ministers were relieved through presidential decrees readout on the state-run SSBC on Friday evening.
In a separate decree, Kiir also discharged the undersecretary in the ministry of trade and industry, Agak Achuil, and appointed him as the new minister of finance in a separate decree.
Kiir appointed Mahmud Solomon, a former governor in the defunct western Lakes state, as the new interior minister, replacing Gen. Paul Mayom Akech.
There were no reasons cited for the dismissal of the two cabinet ministers.
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