Two senior aid workers have been ordered to leave Sudan's restive Darfur province, the International Organization for Migration (IOM) said.
The government's decision comes just days after the International Criminal Court (ICC) issued a new arrest warrant against Sudanese President Omar al-Bashir, adding genocide to list of charges he faces relating to the Darfur conflict, DPA reported.
"No explanation has been given as to why this decision was taken," IOM said in a statement on its website Thursday. "IOM regrets this development which will seriously impact on its capacity to continue its humanitarian work in Darfur."
Following the issue of the first warrant in March 2009, Sudan expelled thirteen aid agencies from the western province - a move which caused uproar amongst charities attempting to care for millions of people displaced by the conflict.
Sudan's Foreign Ministry said that the two workers had violated the terms of the agreement made with the agency that allowed their employment.
IOM did not reveal the identities of the expelled workers, but reports said they were the director of the organization in Darfur and the head of office in South Darfur.
The Sudanese government rejected Monday's warrant, which adds three counts of genocide to five counts of crimes against humanity.
The UN estimates 300,000 people have died in Darfur since 2003, when mainly black mainly non-Arab tribesmen took up arms against what they called decades of neglect and discrimination by the Arab-dominated government in Khartoum.
Even though fighting has died down to sporadic clashes, millions remain in internationally funded camps for fear of revenge attacks by the Arab militias al-Bashir is accused of arming and allowing to run amok.