South Wales Metro being set up to fail says Labour AM
A Labour backbench AM has said he fears the Metro public transport project for South East Wales is "being set-up to fail".
Lee Waters, in a speech making the case against an M4 relief road in Newport, said the plans were being starved of UK government help and EU funds.
He questioned why a public transport system to tackle peak demand on the motorway was not being developed.
Economy Secretary Ken Skates said the M4 infrastructure needed an upgrade.
The Llanelli AM's debate in the assembly on Wednesday comes after the publication of the Welsh Government budget for 2018-19, which said the M4 relief road would be among the projects that could benefit from £375m of borrowing over three years.
Mr Waters, who has previously stated his opposition to the project, urged the Welsh Government not to reject the Future Generation Commissioner Sophie Howe's criticism of the scheme, saying: "If they fight her in the courts they risk undermining their very own landmark legislation".
Ms Howe argued Welsh ministers are misinterpreting the Future Generations Act in their case for a new motorway in Newport.
The Metro project is a proposal for upgraded rail and bus services across South East Wales, would involve the new Wales and Borders rail franchise.
Mr Waters told the chamber that projections for the scheme have taken the most "pessimistic view", while the formula used to justify the relief road have taken "the most optimistic view of the possible benefits".
"Transport officials have suggested to the public inquiry that of the 11,000 journeys made every hour in peak times on the M4 the metro will, at best, only take 200 off the roads," he said.
"I just don't buy it. But even if this really is the case... why are we not setting out to develop a public transport system that will tackle peak hour M4 demand?
"I fear this project is being set up to fail. It is being starved of investment, by the UK government cancelling electrification and by the disappearance of EU grants because of Brexit, and by the road building lobby who are trying to minimise its impact."
Mr Waters said he himself had been stuck in queuing traffic at the Brynglas tunnels - congestion that the M4 relief road aims to solve.
But he said the new motorway would not be anything more than an "expensive stop-gap", fearing that the road could itself become congested and "could end up... a £1bn car park".
He alluded to comments made by the First Minister Carwyn Jones when he said that "bearing in mind two years ago people were insisting that the cost would be 'way below' a billion - it may go up even further".
Responding to the debate, Economy Secretary Ken Skates said the "Metro's greatest positive impact will be on north-south patterns of travel and not the east-west journeys catered for by the M4".
He said that a report found "less than 4% of traffic on the M4 would be extracted from the road".
"The existing infrastructure on the M4 around Newport is not fit for purpose... This piece of infrastructure needs a major, long term upgrade," he added.