Nissan Motor Co. has halted preparations for a business alliance with Chrysler LLC under which the two automakers would build vehicles for each other, the Japanese news agency Kyodo reported Thursday.

Under the planned deal unveiled last year, Nissan was to build small cars for Chrysler, and Chrysler was to build a pickup truck for the Japanese automaker under the Nissan name.

Kyodo, citing unnamed sources close to the deal, reported that Nissan is now reviewing the alliance, with terminating the tie-up an option.

A spokesman for Nissan's U.S. operations said he had not seen the report and could not immediately comment.

Chrysler last year accepted $4 billion in government loans and is racing to develop a viability plan to show to the U.S. government by its Tuesday deadline. The Auburn Hills, Mich.-based automaker also recently announced an alliance with the Italian automaker Fiat SpA.

Under that tentative deal reached in January, Fiat would take a 35 percent stake in Chrysler in exchange for its small-car technology.

Thursday, Frank Klegon, Chrysler's product development chief, conceded the Nissan deal would duplicate some of Fiat's products, but he said Chrysler is still working with the Japanese automaker.