JUBA, Oct. 23 (Xinhua) -- The United Nations humanitarian agency on Friday condemned incidents against humanitarian workers and their activities in South Sudan's Renk, Upper Nile.

Mohamed Ag Ayoya, humanitarian coordinator ad interim in South Sudan, said following an increase in threats against humanitarians and attacks against office, accommodation and warehouse locations, almost 30 aid workers have relocated to the closest UN Mission in South Sudan base for their safety.

Aid workers are in Upper Nile to deliver lifesaving assistance to the most vulnerable people, including women, children and older persons, he said.

"Intimidating them and forcing humanitarian activities to suspend result in delays of this much-needed assistance to the most vulnerable people, and is unacceptable," Ayoya said in a statement issued in Juba.

Tensions between local youth and humanitarian organizations have been building up in Renk in recent weeks.

On Oct. 12, the Renk Youth Association demanded that humanitarian organizations re-assign jobs from current staff from certain backgrounds to local people.

When the demand was not met, the youth then insisted that all humanitarian activities be suspended and aid workers leave Renk immediately without their assets.

Ayoya acknowledged the constructive role played by the national authorities, including the South Sudan Relief and Rehabilitation Commission, who have advocated for the immediate institution of safety for humanitarian workers and resumption of their programs.

"We are working together with national and local authorities, humanitarian organizations and the youth to find a solution to have the needs of crisis-affected people served," he said. "This needs to be resolved immediately."

The UN said humanitarians in Upper Nile continue to experience frequent access issues, primarily due to operational interference and bureaucratic impediments.

These issues, it said, are often related to employment opportunities, also seen in other parts of South Sudan.

Recently, bureaucratic impediments in Upper Nile have led to the suspension of humanitarian activities and relocation of humanitarian workers in Malakal and Melut counties. Enditem