The UN says in its latest weekly humanitarian bulletin for South Sudan that the army is interfering with relief operations in Warrap State.
UNOCHA says the assistance to over 110,000 IDPs is being hampered by logistical and weather challenges.It added that the SPLA is interfering in relief operations along key transport routes.
UNOCHA said it received reports that troop stook or attempted to seize humanitarian vehicles on at least four occasions in Twic and Gogrial West counties in mid-July.
The UN agency added that partners continue to work with the authorities to stem interference.
It asked the SPLA to respect relief vehicles and facilities as weapons free zones.