The medical charity, Medicines Sans Frontier, says it has suspended some of its outreach activities in Malakal County due to increased fighting in the area.
Authorities in the area had reported increased violence between government troops and forces suspected to be loyal to General Johnson Olony.
The United Nations says more than 1,500 people fled to their IDP camps in the area.
“At this moment, the situation in Malakal town remains extremely volatile and it is expected that confrontations will continue in the coming hours,” read a statement.
“MSF teams have today been forced to suspend some of its outreach activities to remote areas hosting internally displaced people,”
MSF says it has decided to suspend its activities in the area because the situation may remain extremely volatile.
“MSF calls upon all parties to the conflict to respect and facilitate access of humanitarian assistance to the people affected by the South Sudanese conflict,” it continued.