The news that the Great Western Main Railway Line is to be electrified as far as Cardiff has been welcomed by local MP Simon Hart.

The electrification, coupled with investment in new trains, will cut 20 minutes off journey times between London and West Wales.

"This is great news," said Mr Hart. "As someone who uses this service regularly I know how important it is to have fast and efficient trains to the West.

"It's not perfect as I would have liked to see electrification as far as Swansea but it is a significant improvement on the record of the previous Labour government, who failed to electrify a single metre of track in Wales despite being in office for 13 years.

"I shall continue to lobby for further electrification and improved services."

The Government has announced that it intends to invest in a new mixed fleet of intercity trains, comprising of some all-electric trains and some electric trains which are also equipped with underfloor diesel engines.

Phillip Hammond, Secretary of State for Transport said: "Because of our decision to proceed with bi-mode trains, journey times from London to Swansea will be shortened to two hours and 39 minutes – 20 minutes faster than today - with trains switching automatically to diesel power as they leave Cardiff."

He also said that there were not enough trains travelling West of Cardiff to make it worth investing in electrification – for the moment.

"At the present time, services to Swansea are insufficiently frequent to make a viable business case. However, in light of our policy of progressive electrification of the rail network, we will keep the situation under review and consider the case for further electrification of the line in the light of future service patterns," he added.