Environmental pressure group Friends of the Earth (FoE) is calling for an immediate halt to the outdoor testing of GM crops following the revelation yesterday [Thursday] that the Aventis GM oilseed rape used in the controversial farmscale trials was contaminated with another GM variety. With the last of the farm scale trials due to be planted next week, FoE supports the call from the government's advisors ACRE (Advisory Committee on Releases to the Environment) for a delay.