The British carriers EE and Vodafone(s vod) have signed a 10-year agreement with the operators of the Channel Tunnel, the 50-kilometer (31-mile) underwater tunnel that links the UK with France, to provide mobile services there.

The deal with Eurotunnel covers the North Running Tunnel, going from the UK to France. French carriers Bouygues Telecom, Orange and SFR struck a similar arrangement covering the South Running Tunnel in 2012, just before the London Olympics.

Echoing that deal, EE and Vodafone said that from March this year they will offer 2G and 3G services to passengers of both high-speed Eurostar passenger trains and Le Shuttle, the rail-bound shuttle service for cars. Both companies said they also intended to offer 4G services in future.

The carriers said they had managed to install the necessary equipment without any disruption to rail traffic, and the quality of calls 100 meters (328 feet) underwater would be…