Britain has opened its first-ever full high-speed rail line from London to the county of Kent, allowing trains to run at 220kmph (140mph).

The $9.4m (£5.8bn) rail route covers 22 towns and is part of the London to Folkestone high-speed rail link built for Eurostar trains through the Channel Tunnel.

The line is served by 29 Japan-built Hitachi class 395 Javelin trains, which cut the journey time on the route by 50 minutes.

The UK plans to invest $32bn (£20bn) in high-speed railway infrastructure in the next few years.