Sudan’s paramilitary Rapid Support Forces and allies have 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.

Sudan's army said on Sunday it had seized back control of the town of el-Gitaina, just south of the capital, from the Rapid Support Forces (RSF) and broken the paramilitary group's siege on the strategic city of el-Obeid to the west.

Activists said three days of attacks by the paramilitary group had killed more than 200 people in White Nile state, which has emerged as a key battleground as the army regains territory.

Sudan's Rapid Support Forces signed a charter with allied political and armed groups late on Saturday to establish a "government of peace and unity", signatories al-Hadi Idris and Ibrahim al-Mirghani told Reuters.

Sudan's paramilitary Rapid Support Forces and its allies have agreed to set up a parallel government, sources said Sunday, despite warnings such a move could further fragment the war-ravaged country.