the competent authority of the F1constituent territory of destination in Great Britain has issued to the user of the samples an authorisation in advance for their introduction into F2Great Britain in accordance with Article 27(1) of Regulation (EU) No 142/2011 and this authorisation is recorded in an official document delivered by that authority;

they are accompanied by the official document referred to in point (a) or by a copy thereof until they reach the user referred to in point (a) or in the case referred to in point (c) the border control post of entry;

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