The transitional period will last until 31 December 2020, and following this the UK will become a third country. Based on current regulations, seed varieties and maintainers must be registered in the Community Varieties Catalogue in at least one EU Member State in order to remain in the common market. This means that if, after the day of the withdrawal, a seed variety is not registered in the EU but only in the United Kingdom, then its free trade within the EU 27 Member States will automatically cease. However, this is not expected to cause problems in practice for plant variety use due to the high degree of substitutability. As the United Kingdom will be considered as a third country as of 1st January 2021, the seed lots will arrive in Hungary with the OECD label. Species that require a plant passport must have a seperate phytosanitary certificate in additional to the label, because this fact can not be indicated on the OECD label itself.