A resolution backed by former colonial power France outlines a new peacekeeping force in CAR and calls on the interim government to stick to plans for elections in early 2015.
The rebel Seleka coalition ousted President Francois Bozize in March.
Marie Harf, a spokeswoman for the U.S. State Department, said unanimous support for the resolution was the first positive step for the troubled nation in a long time.
"We see this as a positive first step towards enabling political stabilization and an end to the ongoing violence in the Central African Republic," she said during her regular press conference Thursday.
The U.S. Embassy in Bangui said in December it temporarily suspended its operations because of the security situation in CAR. Diplomatic ties with the government weren't affected by the closure, though the ambassador and his staff were evacuated.
Interim Prime Minister Nicolas Tiangaye told the U.N. General Assembly last month his country was working hard to address a national system on the verge of collapse.
Adama Dieng and Jennifer Welsh, two U.N. advisers addressing genocide and the protection of civilians, expressed concern last week that "the international community has yet to engage in a concerted way to prevent atrocities in CAR."
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