Fresh fighting has erupted between government and opposition forces in South Sudan just days after both sides pledged to uphold a ceasefire and try to save a teetering peace deal.

The clashes in oil-rich Unity State were the latest in recent weeks between forces allied to President Salva Kiir and those loyal to his deputy, veteran opposition leader Riek Machar.

The pair rule in a power-sharing government that was brokered in the aftermath of a civil war that left nearly 400,000 people dead before a peace agreement paused the bloodshed in 2018.

But the ceasefire has been repeatedly violated and their forces remain largely on opposing sides of the battlefield, raising fears of a return to all-out war between the historic foes.

The latest violence involved militia backed by the national army attacking a garrison for Machar’s Sudan People’s Liberation Army in Opposition (SPLA-IO), according to officials from both sides.

In Juba, top military figures from Kiir and Machar’s camps issued a joint appeal for calm.

“We direct all forces to cease hostilities and uphold the cessation of hostilities agreement,” said Lieutenant General Thoi Chany Reat, deputy chief of South Sudan People’s Defence Forces.