Chrysler and Nissan Motor of Japan said Monday that they had agreed to build vehicles for each other in a deal that could signal closer cooperation in the future.Chrysler, which is based in Auburn Hills, Mich., and has been cutting truck production as demand falls for less fuel-efficient vehicles, will make a full-size pickup based on the Dodge Ram for Nissan at a factory in Saltillo, Mexico. In turn, Nissan will assemble a small car for Chrysler in Oppama, Japan. Both vehicles will be sold in North America, though Chrysler plans to sell the car in Europe and other markets, too.

Officials from both automakers said the deal was limited to these two products, but analysts say Chrysler and Nissan could eventually join forces in many areas of their operations to become more competitive. Nissan has expressed an interest in having a North American partner join its alliance with the French carmaker Renault, since talks with General Motors in 2006 were called off, and Chrysler is eager to expand its footprint outside North America.

“Forging the right tactical partnerships is critical to the long-term success of Chrysler,” said Thomas W. LaSorda, Chrysler’s president and vice chairman. “Nissan has a proven track record in these win-win product exchanges with multiple manufacturers around the world.”

Both vehicles will be designed by the companies that will ultimately sell them. Nissan will begin distributing the car in 2010, and Chrysler will start building the truck, which replaces the Nissan Titan, in 2011.

Mr. LaSorda said Chrysler recently finished designing the car, which will be that automaker’s first offering in the subcompact, or B-segment, category. Sales of small cars have increased rapidly as consumers seek more environmentally friendly and fuel-efficient vehicles at a time when gasoline prices are nearing $4 a gallon.

The Titan is by far the weakest player in the full-size pickup segment, in terms of sales, which have fallen 39 percent so far this year. In contrast, sales of Nissan’s subcompact, the Versa, are up 22 percent.