All expenditure must be liquidated and authorised during the financial year to which it relates. The Agency’s expenditure shall be settled by the Accounting Officer by order of the President of the Agency or after having been accepted by the latter. Expenditure orders shall be supported by the necessary documentary evidence, in particular invoices, briefs, contracts, leases or agreements. Acceptance of the expenditure shall take the form either of a dated and signed statement on the memorandum, invoice or any equivalent document, or of a separate service performance certificate, either of which shall specify that payment may validly be made for the sum indicated.
The accounting officer may pay certain categories of expenditure without prior authorisation or before service has been rendered, in accordance with the conditions laid down in the accounting and financial regulations.