Cardiff rail upgrade value questioned by MP Glyn Davies

New hybrid trains can deliver faster journeys, UK ministers have said

A senior Tory MP has questioned the worth of electrifying the Great Western rail line from London to Cardiff.

Montgomeryshire MP Glyn Davies had "no doubt" a controversial decision to scrap the upgrade between Cardiff and Swansea was correct.

He said the London-Cardiff upgrade, due to be completed by the end of 2018, had been based on "fanciful figures".

Transport Minister Jo Johnson told MPs on Tuesday the project's value for money was positive but "not great".

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Mr Davies is a member of the Welsh Affairs select committee, which has been investigating the decision to end electrification at Cardiff.

The MP, who is also a parliamentary aide to Welsh Secretary Alun Cairns, said: "I've ended up thinking that not only was that decision totally right, but been left wondering how wise it was to electrify the Great Western line from Paddington to Cardiff.

"Because of massive cost over-runs it has only a marginal cost benefit."

However, he conceded there could be an argument about the environmental impact of not upgrading the line.

The original £1.7bn cost of electrification between London and Cardiff has risen to an estimated £2.8bn.

Mr Johnson told the committee on Tuesday that the costs had been "blowing out of control" and that the project's value for money, while positive, was "not great".

In July, Transport Secretary Chris Grayling said faster journeys between London and Swansea would be achieved with new trains.