TOKYO—Toyota Motor Corp. and Mazda Motor Corp. are in talks to share certain technologies, a person knowledgeable about the matter said Sunday, as some auto makers turn to tie-ups with rivals to reduce mounting costs of developing fuel-efficient cars.

Under consideration is a deal in which Toyota would offer its plug-in hybrid and fuel cell technologies to Mazda. In return, Mazda would provide its fuel-efficient gas and diesel engine technologies to Toyota, said the person who spoke on the condition of anonymity.

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