The Railway Board has accorded in-principle approval for the Communications Based Train Control (CBTC) signalling and train control system for Namma Metro's Pink Line, Reach-six, and for the entire Blue Line comprising Phase two A and Phase two B extending to Kempegowda International Airport (KIA), the Bangalore Metro Rail Corporation Limited (BMRCL) said. The approval covers the systems required to enable integrated signalling and train operation across the specified corridors. BMRCL stated that the clearance represents a key regulatory milestone ahead of passenger operations. BMRCL said the in-principle nod is a step towards commissioning the Pink Line section between Kalena Agrahara and Tavarekere and that it has been pursuing final approvals with the Railway Board and the Research Designs and Standards Organisation (RDSO) over the past one month. For the Blue Line, which runs from Central Silk Board to KIA, the signalling clearance had been secured earlier, enabling the authority to proceed with testing and safety work without delay. The corporation indicated that securing CBTC approval was a pending requirement for the Pink Line and has now been addressed. The corporation outlined the remaining statutory and technical steps before passenger services commence on the Pink Line. These include interim speed certification from RDSO, statutory inspection of the rolling stock by the Central Commissioner of Railway Safety (CCRS), and trial runs to validate operations under the CBTC regime. Once these stages are completed and the final statutory inspection is cleared, the line will be opened for public use. BMRCL will continue coordination with the Railway Board and RDSO to expedite completion of the approval process and to schedule the required tests. The clearance is expected to support integrated metro connectivity to the airport and to facilitate timely safety certification across the expanded network. The corporation said it will announce further operational timelines after completing trial runs and regulatory clearances.