Article 18
If it is established that the cultivation of a variety included in the common catalogue of varieties could in any Member State be harmful from the point of view of plant health to the cultivation of other varieties or species, or present a risk for the environment or for human health, that Member State may upon application, be authorised in accordance with the procedure referred to in Article 23(2) or in Article 23(3) in the case of a genetically modified variety to prohibit the marketing of the seed or propagating material of that variety in all or part of its territory. Where there is imminent danger of the spread of harmful organisms or imminent danger for human health or for the environment, that prohibition may be imposed by the Member State concerned as soon as its application has been lodged until such time as a final decision has been taken. That decision shall be taken within a period of three months in accordance with the procedure laid down in Article 23(2) or in Article 23(3) in the case of a genetically modified variety.