4. Where the European Data Protection Supervisor is of the opinion that the intended processing referred to in paragraph 1 would infringe this Regulation or the legal act establishing the Union body, office or agency, in particular where the controller has insufficiently identified or mitigated the risk, the European Data Protection Supervisor shall provide written advice to the controller within a period of up to six weeks of receipt of the request for consultation. That period may be extended by a month, taking into account the complexity of the intended processing. The European Data Protection Supervisor shall inform the controller of any such extension within one month of receipt of the request for consultation, together with the reasons for the delay.