Sudan declared a state of emergency along its border with South Sudan on Sunday, in a move that imposes a trade embargo on the South and suspends the constitution, official news agency SUNA said.
President Omar al-Bashir issued a resolution declaring the emergency in border districts of South Kordofan state, White Nile and Sennar states, it said.
The measure follows a month of border fighting with South Sudan, which separated last July after a peace deal ended one of Africa's longest civil wars, which killed about two million people between 1983 and 2005.
An emergency has already been in effect for almost a decade in Darfur, along the western border with South Sudan, while a similar status took effect in Blue Nile state last September when an ethnic insurgency began.
Trade across the border has unofficially been banned since South Sudan's independence but the emergency formalises that prohibition.
Bashir's resolution "gives the right to the president and anyone with his mandate" to establish special courts, in consultation with the chief justice, SUNA said.
The courts will handle criminal and "terrorist" cases, it added.