In times of crisis, there might be a need for certain specific measures to be taken urgently by providers of very large online platforms, in addition to measures they would be taking in view of their other obligations under this Regulation. In that regard, a crisis should be considered to occur when extraordinary circumstances occur that can lead to a serious threat to public security or public health in the Union or significant parts thereof. Such crises could result from armed conflicts or acts of terrorism, including emerging conflicts or acts of terrorism, natural disasters such as earthquakes and hurricanes, as well as from pandemics and other serious cross-border threats to public health. The Commission should be able to require, upon recommendation by the European Board for Digital Services (‘the Board’), providers of very large online platforms and providers of very large search engines to initiate a crisis response as a matter of urgency. Measures that those providers may identify and consider applying may include, for example, adapting content moderation processes and increasing the resources dedicated to content moderation, adapting terms and conditions, relevant algorithmic systems and advertising systems, further intensifying cooperation with trusted flaggers, taking awareness-raising measures and promoting trusted information and adapting the design of their online interfaces. The necessary requirements should be provided for to ensure that such measures are taken within a very short time frame and that the crisis response mechanism is only used where, and to the extent that, this is strictly necessary and any measures taken under this mechanism are effective and proportionate, taking due account of the rights and legitimate interests of all parties concerned. The use of the mechanism should be without prejudice to the other provisions of this Regulation, such as those on risk assessments and mitigation measures and the enforcement thereof and those on crisis protocols.