101. WP. 29 endorsed the proposal of the Chair of GRPE for establishing an informal working group on Vehicle Propulsion System Definitions (VPSD), under the chairmanship of Germany (WP.29-156-26). The World Forum approved the terms of reference of the informal working group as reproduced below:

1. VPSD under GRPE will be chaired by Germany, participation is open for everybody.
2. VPSD will work in close cooperation with the informal working group on Worldwide harmonized Light vehicles Test Procedures, subgroup on the Development of the Test Procedure (WLTP-DTP) and the WLTP drafting manager. (c) VPSD shall: * (i) Review existing UN Regulations and UN GTRs concerning terms, definitions and classifications regarding vehicle propulsion systems. * (ii) Review the related definitions in the current draft of the WLTP GTR. * (iii) Develop a proposal for a frame system of terms, definitions and classifications regarding vehicle propulsion systems for the introduction into the Consolidated Resolution on the Construction of Vehicles (R.E.3) and on the Special Resolution No. 1 (S.R.1).