Luka Biong Deng, co-chairman of the Abyei Joint Oversight Committee, said the creation by Sudan of a humanitarian commission was done only to more easily settle members of the Misseriya tribe in the area, the Sudan Tribune reported Sunday.
Deng said the unilateral creation of the commission violates a June 2011 agreement that specifies an interagency task force.
Deng said United Nations peacekeeping forces in Abyei should report Sudan was in "clear violation" of the agreement by sending more troops into the region instead withdrawing them as required.
"The people of Abyei have suffered a lot," he said. "It is time for the international community to give them [the] support they deserve."
South Sudan's president, Salva Kiir, has accepted an African Union proposal to hold a referendum in October for the residents of Abyei to decide which country the region should join.
The AU proposal would restrict the Misseriya from voting because they are not permanent residents of the area.