Suspected Islamist militants killed 25 soldiers and wounded six others in an attack on an army outpost in west Niger near its border with Mali on Thursday, the government said in a statement.
It was not immediately clear who was responsible for the attack, in which 63 assailants were also killed, the statement said.
But it comes amid a concerted campaign by Islamist groups connected to al Qaeda and Islamic State against the Nigerien army on its western frontier.