Minister of Information Barnaba Marial Benjamin said the move by President Salva Kiir Mayardit was constitutional, Voice of America reported Wednesday.
"He has acted within the constitution of the Republic of South Sudan," Benjamin said.
He said President Mayardit has appointed the secretary general and the undersecretary to administer the government until a new government has been formed.
A government makeover was long overdue, Benjamin said, rejecting suggestions the reshuffle might cause instability in the world's youngest country.
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