The Working Party on Noise and Tyres held its eighty-fourth session from 2-4 September 2026 in Geneva. GRBP adopted a draft new Supplement to the 02 series and a draft new Supplement to the 04 series of amendments to UN R117, and agreed to submit these to WP.29 and AC.1 for consideration and vote at their March 2027 sessions. GRBP adopted the content of a proposal for a new supplement to UN R64 and agreed to postpone submission to WP.29 until further notice. GRBP adopted revised Terms of Reference for the IWG on Real Driving-Additional Sound Emission Provisions with extended mandate until February 2028.