Clashes have erupted between the army and rebels in the western Darfur region and a southern state, killing dozens of people including civilians.

President Omar Hassan al-Bashir is battling an alliance of rebel groups in Darfur and two states bordering South Sudan, which Sudan accuses of supporting the rebels, while it in turn says Khartoum funds militias in South Sudan.

South Sudan split from Sudan last year under a 2005 peace deal that ended decades of civil war, but the two have remained at odds over a range of issues.