Vermont has become the first US state to require genetically modified seeds to be labelled.

Under new legislation, signed this week by Governor James Douglas, all genetically modified or engineered seeds must be labelled as such after 1 October, reported Dow Jones International News.

Some environmental groups had been hoping for a moratorium on the sale of GM seeds, and the labelling law was seen as a compromise.

Sales of genetically modified seeds in Vermont must also be reported to the state’s secretary of agriculture each year.