Vehicle-to-Everything (V2X) communications has the potential to increase the safety and autonomy of automated vehicles in addition to improving reliability, efficiency, infotainment, traffic, road safety, energy consumption, and costs. V2X is enabled by 5G technologies which promise faster connections, lower latency, higher reliability, more capacity and wider coverage. However, research is lacking in determining exactly how V2X can improve the safety, security, and autonomy of automated vehicles and more specifically what are the main V2X requirements. This paper provides a novel framework and structure to introduce V2X as a perception sensor sub-system into ADAS and ADS and to allocate top level target safety requirements to this new modality. To illustrate the novel structure, an example is provided using AD use cases in the context of the five SAE driving automation levels Level 1 through Level 5. The design follows methodologies from standards and regulations such as ISO 26262 (Functional Safety), ISO 21448 (SOTIF), ISO 34502 (Test scenarios for automated driving), UNECE R-157 (Lane keeping assist system) and R-152 (Autonomous emergency braking) are considered. Following the new novel structure, a set of V2X requirements related to the functional safety of an autonomous emergency braking functionality of an automated vehicle are derived. Mapping the V2X requirements to specific 5G technologies such as IEEE 801.11p, C-V2X, and NR-V2X is out of scope of the paper.