Lockheed Martin Corp. is in the final stages of negotiating a deal worth more than $37 billion to sell a record 440 F-35 fighter jets to a group of 11 nations, including the United States, two people familiar with the talks said.

This would be the biggest deal yet for the stealthy F-35 jet, set to make its Paris Airshow debut this week. The sale represents a major shift in sales practices from annual purchases to more economic multiyear deals that lower the cost of each jet.

The pricing of the jets was still not final, although the average price of the 440 jets was expected to be $85 million, the people said on condition of anonymity because they were not authorized to discuss the negotiations publicly.