The UN Undersecretary-General for Peacekeeping Operations said no progress had been made over the final status of the disputed Abyei region, despite improved relations between Sudan and South Sudan.
Abyei is a contested territory between Sudan and South Sudan.
"No meetings of the Abyei Joint Oversight Committee have taken place since November 2017. No progress has been made in the establishment of joint governance institutions, including the police, the court, and the corrections, either," Jean-Pierre Lacroix told the Security Council on Thursday in New York.
He said although Sudan and South Sudan relations have improved recently, it has not been extended to the Abyei question.
"Building upon the recent positive developments in their bilateral relations, the two sides need to resume direct talks immediately to resolve the outstanding provisions of their agreement about the final status of Abyei and border issues," he added.
According to Lacroix, South Sudan has been adamant in participating in a joint planning exercise despite Sudan's willingness.
The UN official also asked for a postponement of a planned reduction of forces for the UN Interim Security Force for Abyei (UNISFA) saying UNISFA requires sufficient force to fulfill its mandate.
Sudan and South Sudan failed to jointly organize a self-determination referendum in 2011 in Abyei as per the 2005 Comprehensive Peace Agreement of 2005.