1.Where it is compulsory for a guarantee to be provided, and subject to the rules adopted pursuant to paragraph 3, the customs authorities shall fix the amount of such guarantee at a level equal to the precise amount of import or export duty corresponding to the customs debt and of other charges where that amount can be established with certainty at the time when the guarantee is required.
Where it is not possible to establish the precise amount, the guarantee shall be fixed at the maximum amount, as estimated by the customs authorities, of import or export duty corresponding to the customs debt and of other charges which have been or may be incurred.
2.Without prejudice to Article 62, where a comprehensive guarantee is provided for the amount of import or export duty corresponding to customs debts and other charges which vary in amount over time, the amount of such guarantee shall be set at a level enabling the amount of import or export duty corresponding to customs debts and other charges to be covered at all times.
3.The Commission shall, in accordance with the regulatory procedure referred to in Article 184(2), adopt measures for the implementation of paragraph 1 of this Article.