1.   The requesting authority and the requested authority shall communicate in relation to a request for assistance and its reply by the most expedient means, taking due account of confidentiality considerations, correspondence times, the volume of material to be communicated and the ease of access to the information by the requesting authority. In particular, the requesting authority shall respond promptly to any clarifications requested by the requested authority.

2.   When the requested authority becomes aware of circumstances that may lead to a delay in its estimated date of response of more than 10 working days, it shall notify the requesting authority without undue delay.

3.   Where appropriate, the requested authority shall provide regular feedback regarding progress of the pending request, including revised estimates of the targeted date of reply to the requesting authority.

4.   Where the request has been qualified by the requesting authority as urgent, competent authorities shall consult each other on the frequency with which the requested authority will update the requesting authority.

5.   The requested authority and the requesting authority shall cooperate in order to resolve any difficulties that may arise in executing a request.