Anyone going to the United States on official business for a government or designated international organization must obtain an A or G visa.
Anyone assigned to a foreign embassy or consulate and any national government official on a temporary mission in the U.S. is required to have an A visa. Local government officials representing their region, department, commune, or other local political entity do not qualify for A visas and require a visitor (B) visa.
Individuals representing their government at, or hired to work directly for, certain designated international organizations located in the U.S. are required to have G visas. Employees of these organizations stationed outside the U.S. who travel to the U.S. temporarily for their work are also required to obtain G visas. Contact the Consular Section at ConsulateNiamey@state.gov or 20-72-26-61 if you are uncertain if your organization is one of those designated for G visas.
Only travel to the U.S. to perform official duties is permitted with A and G visas. Officials travelling to perform non-governmental functions of a commercial nature, or travelling as tourists, do not qualify for A or G visas. These individuals must apply for the visa category for their specific travel purpose.