Hundreds of thousands of refugees in Darfur are facing the prospect of their food, medicine and water supplies drying up after the Sudanese government expelled at least 13 aid agencies from the region, the banished groups warned on Thursday.

An Arab man expresses his support for Omar al-Bashir, Sudan’s president, during a rally in Khartoum

The expulsions started hours after Omar al-Bashir, Sudan’s president, became the first sitting head of state to be indicted by the International Criminal Court when it issued an arrest warrant for him over atrocities in Darfur.