With Nissan's chief operating officer, Ashwani Gupta, having helped engineer the troubled automaker's latest turnaround plan, his allies are now pressing the board to promote him to co-CEO to drive the new strategy, four people with direct knowledge of the matter have said.

So far, Nissan Motor Co's 12-member board has no plan to change the roles of Chief Executive Makoto Uchida or his No. 2, Gupta, the sources told Reuters.

But the behind-the-scenes campaign, involving at least half a dozen current and former executives, points to continued tensions at the top of the automaker, which has had four CEOs in as many years.