Trade in Daihatsu shares was set to resume later in the morning.
Toyota and Suzuki are looking to take advantage of each other's know-how and capitalize on demand for compact cars in India and other emerging economies, the Nikkei said without citing sources.
Suzuki, which specializes in small cars, is India's top-selling car maker through its local unit Maruti Suzuki India.
But the automaker has long been under pressure to find a bigger partner to develop next-generation fuel-saving technology as governments around the world tighten emissions and fuel economy regulations.
Suzuki formed a capital alliance with Volkswagen in early 2010 but relations soon soured, leading to a years-long dispute in arbitration court that ended last year with the unwinding of their cross-shareholding.
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