PLAID Cymru has called for government pledges that the Valley train line electrification will go ahead – despite more than £100 million in funding due to come from the EU.

Party leader Leanne Wood today warned the planned electrification project – which would modernise the railway line from Cardiff to Ebbw Vale– “must not become a casualty of Brexit”.

The electrification is part of the South Wales metro project, one of the key promises of the £1.2 billion Cardiff Capital City Region deal which is in the pipeline.

£734 million of the money for the next phase of the metro project, which includes the Valley line electrification, was set to come from the city deal – but more than £100 million was expected to come from the EU.

Ms Wood said her party will press both the Welsh and UK governments to ensure any loss of EU funds to Wales is compensated in full.

Work to electrify the Valley lines was planned to begin in 2019 and completed by 2023. The Cardiff route to Ebbw Vale, via Rogerstone, Risca and Pontymister, Crosskeys, Newbridge and Llanhilleth, would be one of the routes electrified.

Plaid Cymru said following the result of the referendum there are concerns whether the funding will be replaced. She has called on both the Welsh and UK governments to pledge the money will be replaced.

In the run up to the referendum, leave campaigners said all EU funds available to Wales would be replaced by alternate finance.

“This the biggest transport issue facing Wales," said Ms Wood.

“The whole of Wales is in this together, and Valley Lines electrification must not become a casualty of Brexit.

“Put simply, if it is delayed or scaled down, it means we will continue to be stuck with bad quality, slow and overcrowded trains. But our rail fares won’t go down.”

She said the benefits of electrification will include greener and more modern trains and stations.

She added: “The Welsh Government must fight to ensure the electrification of the Valley Lines is not sacrificed to suit the desires of the UK Treasury.

“Neither should they allow the UK Government to short-change Wales by postponing the electrification of the Valley Lines - as they have already done with electrification of the Great Western Mainline west of Cardiff to Swansea. The valleys can’t afford to lose out yet again.”

A Welsh Government spokesperson said: “The First Minister has met the Prime Minister and has made it repeatedly clear to the UK government that Wales should not lose a penny of the £650m budgeted for Wales from EU programmes from the current EU budget cycle ending in 2020.

"This was a funding pledge made by the leave campaign and, providing this commitment is honoured by the UK Government, the electrification of the valleys line will go ahead as planned, forming part of our fully integrated south Wales metro project.”

The UK Department for Transport was also contacted for comment.