Farm minister Yoshimasa Hayashi said Tuesday he has received a letter from his U.S. counterpart asking Japan to resume wheat imports that have been suspended following the discovery of a genetically modified version of the grain at an Oregon farm.

The letter from U.S. Secretary of Agriculture Tom Vilsack said the discovery of genetically modified wheat was a singular case that occurred only at one farm and no such wheat has been found to have entered the market, Hayashi said.

"If the U.S. government releases the results of detailed investigations and establishes inspection methods, we would like to send our staff to (the U.S.) and consider the timing" to resume imports, Hayashi said.

Japan, a major importer of U.S. wheat, suspended imports of western white wheat in late May after the modified grain was found.

Of the some 5 million tons of wheat Japan imports every year, about 3 million tons come from the United States, and approximately 800,000 tons of it is western white wheat, according to the Agriculture, Forestry and Fisheries Ministry.