The spokesman for the UN secretary-general says the investigation is looking into how many peacekeepers were involved. Stephane Dujarric did not say how many troop-contributing countries had peacekeepers accused in the allegations. The UN is asking the countries to immediately investigate.
The new allegations follow a series of sexual abuse allegations against UN peacekeepers last year in Central African Republic, which has suffered years of sectarian violence.
The UN says a fact-finding mission is under way.