The European Commission said Thursday it has asked EU member states to check imports of wheat from the United States which may be tainted with a genetically modified strain made by US agrochemicals giant Monsanto.
The Commission, the European Union's executive arm, said it had informed the 27 member states of the problem, "recommending (they) test the consignment of soft white wheat" in question.
"In case of a positive confirmed result, the consignment shall not be placed on the market," it said in a statement.
Soft white wheat accounts for about 80 percent of US wheat imported annually by the EU, with most of it going to Spain.
The Commission noted that there "are no GM wheat varieties approved for sale or in commercial production in the United States or elsewhere at this time."
It had contacted the US Department of Agriculture to ask to be kept informed and had also got in touch with Monsanto, it said.
"The Commission is following carefully the presence of this non-authorised GM wheat in Oregon in order to ensure that European consumers are protected ... and to make sure that the EU zero tolerance for such GM events is implemented."
The EU currently allows only two GM products to be grown in the bloc—Monsanto's MON 810 maize and German conglomerate BASF's Amflora potato.
Renewal of the maize licence is currently on hold due to hostility or reticence by a string of EU states.
Brussels cleared MON 810 in 1998 for 10 years and Monsanto submitted a request in 2007 for it to be extended but the process has been effectively frozen.
Explore further: Simplifying SNP discovery in the cotton genome