U.N. peacekeepers will remain in the disputed Abyei region on the Sudan-South Sudan border for another six months, but the Security Council is trimming the force while encouraging the two nations to resolve their stalemate over the oil-rich area.

The council unanimously agreed Tuesday to extend the peacekeeping mission until mid-November. But the renewal lowers the troop ceiling to 4,500 from nearly 4,800 and "expresses disappointment" at the pace of progress toward a political resolution.

The mission is known as UNISFA. It has been in Abyei since 2011.

A decades-long civil war between Sudan's north and south ended with a 2005 peace deal that allowed for South Sudan to become independent. The pact also required both sides to work out the final status of Abyei, but it's still unresolved.