NHK sources say former Nissan head Carlos Ghosn intends to resign from his position as the chairman and CEO of Renault.
Ghosn has been held in detention in Tokyo for over 2 months on a series of financial misconduct allegations.
He was ousted from his post as Nissan chairman after his arrest in mid-November, but Renault has kept him on board.
Ghosn oversaw the alliance between Nissan, Renault and Mitsubishi Motors.
The news comes as the French automaker prepares to hold a board meeting on Thursday to replace Ghosn.
The French government is Renault's largest shareholder. It's urging the company to appoint new management to ensure stability.
French media say tire manufacturer Michelin's chief executive will likely take over as chairman. And Renault's Chief Operating Officer is expected to become CEO. He has been filling in for Ghosn as acting chief executive.
Ghosn's expected departure is likely to intensify a power struggle and talks over the future of the alliance.
Renault owns 43 percent of Nissan's shares, but the Japanese automaker is more profitable. So there have been calls from within Nissan to review the partnership and possibly become more independent.