Ukrainian forces and Russian-backed separatists in the country’s east have undertaken an exchange of prisoners in a step that observers hope will help push the two sides towards a peace deal to end their conflict, which has lasted for more than five years.

The prisoner swap, billed as an “all-for-all” exchange between Kyiv and the two Kremlin-supported breakaway eastern regions, was brokered during talks this month between the leaders of Ukraine, Russia, France and Germany, amid renewed efforts to reach a ceasefire.

The first of scores of prisoners to change hands crossed through a checkpoint on the front line of the conflict on Sunday afternoon, watched over by armed troops from both sides. Live footage streamed over the internet by Ukraine’s presidential office showed buses with prisoners parked at a crossing point.