Great Western's high speed future in the Thames Valley

A multi-billion pound contract has been signed to introduce high-speed trains on the Great Western Main line through the Thames Valley.

The government has agreed a £4.5bn deal with Hitachi - which operates bullet trains in Japan - to provide the new trains by 2017.

First Great Western says journey times will be cut and more seats created.

The high-speed trains will replace a fleet of InterCity trains from the 1970s on the Great Western Main line.