PARIS — Fiat Chrysler proposed on Monday to merge with France’s Renault to create the world’s third-biggest automaker, worth $40 billion, and combine forces in the race to make electric and autonomous vehicles.

The merged company would reshape the global industry: it would produce some 8.7 million vehicles a year, leapfrogging General Motors and trailing only Volkswagen and Toyota.

Shares of both companies jumped on the news of the offer, which would see each side’s shareholders split ownership in the new manufacturer.

Renault welcomed what it called a “friendly” offer. The company’s board met Monday at its headquarters outside Paris and said afterward that Renault will study the proposal “with interest.” In a statement, Renault said such a fusion could “improve Renault’s industrial footprint and be a generator of additional value for the Alliance” with Japan’s Nissan and Mitsubishi.

Fiat Chrysler’s offer comes at a key moment for Renault. The French manufacturer had wanted to merge fully with Nissan, but those plans were derailed by the arrest of boss Carlos Ghosn on financial misconduct charges in Japan.

Now, questions are growing over the Renault-Nissan-Mitsubishi alliance, which together make more passenger cars than any one company. While Fiat Chrysler says the merger with Renault would accommodate the alliance and lead to savings for them, it is unclear how the Japanese companies might react in the longer term to being tied to a much larger partner.

Automakers have collaborated more in recent years as they come under pressure to invest heavily in developing electric cars, self-driving vehicles and in-car connectivity. Regulators, particularly in Europe and China, are pushing automakers to produce electric vehicles and meet tougher climate change regulations, pressure that only grew after scandals over the amount of pollutants emitted by gas and diesel-powered engines.

A deal would save 5 billion euros ($5.6 billion) a year for the merged companies by sharing research, purchasing costs and other activities, Fiat Chrysler said. It promised the deal would involve no plant closures, but it didn’t address potential job cuts.

The companies are largely complementary: Fiat Chrysler is stronger in the U.S. and SUV markets, while Renault is stronger in Europe and in developing electric vehicles. Analysts say both companies are weak in China, which is now the world’s largest auto market.