The Geneva Grand Council has voted unanimously to call on Bern to include an upgrade to the train line running between Geneva and Lausanne.
A similar text has already been approved by canton Vaud.
The issue was brought into sharp focus a few weeks ago after a sinkhole closed the line at Tolochenaz causing widespread disruption.
Geneva deputies say it’s been clear for decades the line was under severe pressure and a vital link for the region. Green party members say if the problems aren’t resolved people will continue using the car.