According to Bloomberg News, Tavares, 55, had proposed a wider role for himself at Renault, an idea Ghosn, 59, rejected. He was offered the chance to remain chief operating officer but ultimately chose to leave in search of a top job elsewhere.

Clearly, constituencies inside Renault, including employee unions, were shocked and disgruntled by Tavares’s statements, which lately have been picked up by the French press.

French labor union members at Renault expressed indignation that Tavares would voice a desire to work elsewhere, especially because he has been a central figure in negotiations for wrenching cost cuts and a personnel freeze at the automaker.

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Force Ouvriere, the third largest French union, distributed leaflets (prior to the news of Tavares’s departure) that read “How do we stay faithful to a head of operations who, by sheer personal ambition, already has one eye looking hungrily at our competitors?”

Tavares has been highly regarded in industry circles. He distinguished himself at Nissan Motors, which is 43% owned by Renault. He may well land a job at another automaker, though presumably he would hire on with a company that needs a new chief executive or at least is willing to make him a contender for that office.

But some automakers could see Tavares as a potential disruption to the corporate suite, a loose cannon who breached customary protocol and displayed questionable judgment by openly discussing his career ambitions in the press.

GM was quick to say that Tavares “isn’t coming here,” in the words of a spokesman. And Ford declined to discuss the matter.

This is the second dust-up in Renault’s executive suite over the past two years. Tavares was promoted to chief operating officer after Renault forced out Patrick Pelata, Ghosn’s erstwhile No. 2, in the wake of a corporate espionage scandal in which three Renault managers were wrongfully terminated.

For Renault and Nissan, Tavares’s exit is certain have repercussions to the company’s succession plans. Carlos Ghosn’s current employment contract expires in April, and as the longest-serving CEO among the top global automakers, he appears to be solidly entrenched. Yet the boards of Nissan and Renault now must reconsider succession at both automakers for the second time in two years.

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Whatever happens next to Tavares, it may not happen quickly. Controversies and passions need a bit of time to fade. Floundering French automaker Peugeot SA could probably use him right now.

As for Ghosn, he displayed his leadership chops again by decisively excising a compromised subordinate before the affair could fester and take an unexpected turn. Just over a year ago, he poached a key executive from Audi to lead Nissan’s luxury-car makeover for Infiniti — perhaps now he will be on the prowl again.