Nissan shares soared more than 20 percent on Wednesday amid media reports it is exploring merger talks with fellow Japanese automaker Honda.

In early trade, Nissan was up 20.97 percent at 408.4 yen ($2.65). Honda shares were down 1.28 percent at 1,267.0 yen, while Mitsubishi Motors -- in which Nissan owns a stake -- was up 13.97 percent at 464.1 yen.