U.S. rice farmers have found an unlikely ally in their endeavor to penetrate Japan's heavily protected rice market -- owners of mom-and-pop rice shops who themselves are bearing the brunt of the nation's market-opening reforms.

Whether the alliance will last remains a question mark, as the two sides appear to have different perceptions of its future.

The USA Rice Federation, which represents more than 80 percent of all rice growers in the United States, recently launched an "American rice shop network" campaign, in which 44 shops in Tokyo and Kanagawa, Saitama and Kyoto prefectures have agreed to sell Akitakomachi and Koshihikari varieties grown in California specifically for the Japanese market.