Tiangaye said his country is on the brink of collapse because of humanitarian and national security challenges.
The International Federation for Human Rights, known by its French initials FIDH, published a 49-page report on CAR this week saying the current state of lawlessness "will have disastrous consequences" if left unresolved.
The rebel Seleka coalition toppled the government this year. It's suspected of committing war crimes in the country, prompting the International Criminal Court to investigate.
Tiangaye said a transitional system is in place to ensure a national system of government is established to take action against Seleka and reintegrate other rebel groups in the country. He told the 68th session of the U.N. General Assembly, however, his nation was "crumbling."
Echoing comments from the government of neighboring Democratic Republic of Congo, Tiangaye said Thursday development can't take place in a security vacuum.
Most of the CAR population relies on humanitarian assistance. The prime minister said the humanitarian situation is "catastrophic," with more than 10 percent of the population coping with a food crisis.
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