63. The GRPE Chair and the IWVTA Ambassador reported on the IWVTA development process, explaining that the objective to extend the mutual recognition of vehicle systems and components to whole vehicles could not be achieved in a single step. UN Regulation No. 0 will therefore allow, in a first step, a partial IWVTA, limited to M₁ category of vehicles and requiring completion by national or regional approvals. The possibility of a complete whole vehicle approval is foreseen for a later stage. The structure of UN Regulation No. 0 includes two tentative lists with UN Regulations that would need to be complied with for obtaining a Whole Vehicle Type Approval: thirty-nine UN Regulations could already be included in the first step of the partial IWVTA (list A), while fourteen UN Regulations (list B) need amendment before their inclusion into list A. The GRPE Chair clarified that no action is needed from GRPE at the moment. Future action needs for GRPE shall be monitored and reported to GRPE by the GRPE Chair and IWVTA Ambassador.