PARTIALLY closing junction 26 of the M4 at Malpas may be a solution to traffic problems around the Brynglas Tunnels, Plaid Cymru leader Adam Price has suggested.

Mr Price, a vocal opponent of plans for an M4 relief road, made the comments in the Assembly earlier this week.

Claiming closing the eastbound slip road onto the motorway and the westbound slip road off it would cut traffic through the often-congested tunnels by up to 40 per cent, Mr Price said building the so-called black route would amount to "saddling future generations in Wales not just with a huge massive negative legacy in terms of the environment".

"Can I suggest a rather neat and exceedingly cheap solution to the whole problem? That's simply to partially close the junction 26 High Cross interchange next to the Brynglas Tunnels," he said.

"This would mean closing the eastbound slip road and the westbound exit slip road."

A Plaid Cymru spokeswoman has clarified Mr Price was referring to junction 26 at Malpas, rather than junction 27 at High Cross.

Addressing leader of the house Julie James, who was standing in for Carwyn Jones during First Minister's Questions, Mr Price added: "We could use some of the money saved to help Newport become a less car-dependent city.

"Do you agree that an up to date study into this idea, and, indeed, complementary changes to the road network south of Newport, and, crucially, investment in our public transport network would be a good way out of the M4 impasse in which you are clearly stuck?"

Ms James replied: "I don't think we are at an impasse.

"We're at a particular point in a decision-making process that is extremely complex."

Professor Stuart Cole, who was the brains behind the alternative blue route scheme, which would involve converting the Southern Distributor Road and Steelworks Road into a dual carriageway, said part of the reason for high volumes of traffic around the tunnels was drivers using the motorway as a ring road.

"For the people of Newport it's a way of getting from one side of the city to another," he said.

"Whether this idea would reduce the traffic by (40 per cent) I couldn't say. But it would certainly reduce it by an amount."

A decision on the project has been repeatedly pushed back. Although Carwyn Jones had repeatedly promised he would decide on the scheme before he leaves office as first minister, this will now not happen before he steps down on Tuesday, December 11.

The report of the public inquiry into the scheme has reportedly not yet been seen by ministers or AMs, and the Assembly has been promised a vote on the project.