The Japan Agricultural Cooperatives group and wholesalers are stepping up efforts to export rice to China, the world's largest rice-consuming nation, as the domestic market shrinks.

Dealers are tying up with Chinese companies and promoting high-priced, high-quality rice on the back of a Japanese food boom in China, although concerns remain over the impact of deteriorating U.S.-China relations on Japan-China ties.

According to Japan's agriculture ministry, Japanese rice costs two to three times more than rice grown in China or the United States. Export costs make Japanese rice even more expensive in overseas markets.