A second tube, parallel to the existing one at a distance of , is under construction. Work began in 2009, following EU regulations put in place after the Mont Blanc Tunnel fire. Originally planned as an wide rescue tunnel, an agreement was reached in 2012 to open the new tube to traffic towards France while converting one lane of the existing tube into an emergency lane. The breakthrough occurred on 17 November 2014. The new tube is due to open to traffic on October 1, 2021 at the earliest. As there will still be a single lane for each direction (the other lane being an emergency lane), the capacity of the tunnel will remain unchanged. Both tubes will be connected by a series of passages, five of which can be used by emergency vehicles.