Sudan’s paramilitary Rapid Support Forces and allies on Sunday signed a charter that paved the way for the establishment of a parallel government, as Sudan's army made advances recently against the rival groups.

The RSF has seized most of the western Darfur region and swathes of the Kordofan region in an almost-two-year war, but it is being pushed back from central Sudan by the Sudanese army, which has condemned the formation of a parallel government.

The move comes nearly two years into a devastating war with the regular army that has uprooted more than 12 million people and caused what the United Nations calls the world's worst hunger and displacement crises.