In a news conference, chief executive Hiroto Saikawa said the job cuts would account for a “big portion” of the savings it was trying to make.
Of the 12,500 job losses, 6,400 have already been implemented at eight locations, he said.
Nissan plans to shed another 6,100 jobs between the 2020 and 2022 financial years at six locations.
He did not specify which models would be targeted for production cuts, but said they would be likely to affect “compact cars and its Datsun range”.
The cuts will fall on unprofitable models, Mr Saikawa added