Shortly after 9 p.m., as the sun began to set on the rotund glass facade housing Renault SA's headquarters on the outskirts of Paris, the board called a break. The group had gathered for the second time in as many days to sign off on a proposed merger with Fiat Chrysler Automobiles NV. As the talks dragged on, Martin Vial, a delegate for the state, asked to liaise with Finance Minister Bruno Le Maire, who was having dinner back in town at his hulking ministry that protrudes into the River Seine.

Le Maire laid down a red line for Vial, who as his representative at the table was the voice of Renault's biggest and most powerful shareholder. France wanted a commitment from Renault partner Nissan Motor Co. to back the combination. Abstention — as had been signaled earlier by the Japanese firm — wasn't good enough, Le Maire said, fearing that Nissan might begin undermining the alliance if it could not be held accountable with a firm vote.

Back in the conference room, the servings of sushi and pizza sourced by security guards had lost their appeal by the time the group reconvened at around 11 p.m. The mood, too, was drab. It quickly became clear that Nissan would, in fact, abstain in a vote. When Vial's turn came to speak, he presented to the panel the government's game plan.