European Union ministers have hit deadlock on whether to let a new strain of genetically modified maize be grown on EU soil for human consumption.

The minister’s vote clears the way for the bloc's executive arm to approve the crop automatically.     

European Commission endorsement of insect-resistant Pioneer 1507, developed jointly by DuPont and Dow Chemical, would end a decade-long debate and break Monsanto's monopoly in Europe's small market for GMO crops.

Although widely grown in the Americas and Asia, GM crops are generally unpopular in Europe, where public opposition is strong and environmentalists have raised concerns about the impact on biodiversity.    

Ministers and diplomats from 19 of the 28 EU countries opposed approval, but under the bloc's weighted voting system, that was not enough to reject the crop.       

Instead, the Commission is now legally obliged to approve it, European Health Commissioner Tonio Borg said.

He said he could not specify when, although EU rules state the Commission must decide "without undue delay".                        

DuPont Pioneer said in a statement that the EU had "a legal obligation to itself, to its farmers and scientists and to its trade partners" to support the approval of safe new agricultural products.       

EU authorities have only ever approved two other GMO crops for commercial cultivation: a maize type and a potato. The potato was later blocked by a court.

Environmental group Greenpeace has claimed that would be "utterly irresponsible" as the EU's own tests suggest the maize is "harmful to butterflies and moths".