IWG CLIV Phase 2 addresses development of a UN Regulation for buses and coaches. The 13th through 17th sessions, held between virtual and in-person meetings from March to May 2026, focused on drafting the bus UN Regulation, refining text on scope, definitions, visual signals, and transitional provisions. Feedback from GRE and GRSG identified scope clarity issues and potential amendments to UN R48. Formal submission of a UN Regulation for buses is anticipated at the 80th GRSP session, with feedback requested before 10 June 2026, and subsequent drafting of a UN Regulation for light vehicles is planned to commence in the second half of 2026.