The Nigerian army's spokesman declared the recapture of a strategic border town of Malam Fatori from Boko Haram militants.
He said soldiers from Chad and Niger drove the Boko Haram militants from the town after fierce clashes.
It is deemed a significant victory, as Malam Fatori was one of the insurgency's last footholds in northeastern Nigeria, the spokesman added.
A joint offensive by Nigeria and its neighbors has succeeded in driving the militants from most of the positions they held earlier this year, an advance that forced Nigeria to delay a February election.