The International Criminal Court's chief prosecutor has urged the UN Security Council to push for the arrest of two Sudanese men indicted for war crimes in Darfur.
Luis Moreno-Ocampo said Khartoum had failed to apprehend former minister Ahmed Haroun and Janjaweed militia leader Ali Kushayb.
The two men were indicted by the ICC in 2007 for war crimes and crimess against humanity.
Khartoum has rejected the indictments.
Sudan, whose President Omar al-Bashir is also wanted by the ICC, is refusing to co-operate with the court.
The government has always denied reports that it had backed the Janjaweed militias accused of widespread atrocities against civilians in Darfur.
More than two million people have been forced from their homes and an estimated 300,000 have died since black African groups took up arms in 2003, complaining of discrimination by the Arab-dominated government in Khartoum.