In a surprise announcement, Japan Tobacco Inc. and instant noodle maker Nissin Food Products Co. said Wednesday that due to the widening "gyoza" dumpling scare, they have scrapped plans to merge their frozen food divisions.

JT President Hiroshi Kimura meanwhile denied that insider trading involving JT shares had occurred early last week, when the stock price fell and before a subsidiary announced it was recalling its frozen gyoza products.

JT decided not to go ahead with a November agreement to sell 49 percent of struggling frozen food maker Katokichi Co. to Nissin and then combine their frozen-food units.