Plaid Cymru are calling on the Welsh Government to reopen its consultation on an M4 relief road around Newport, to allow consideration of the so-called blue route - an upgrade of the city's existing southern distributor road.
Plaid argue that it would be cheaper and quicker to build.
This would be a significant and exciting boost to the economy around the city, and would give traffic an alternative route when the M4 becomes too congested.
The FSB and IoD have backed this proposal and it is a much quicker and decisive way of dealing with the congestion than building a new M4, which would not open until 2031.
The other benefit of the Blue Route is that it protects the sensitive environmental sites on the Gwent Levels.
It is hard to put a financial cost on saving the Gwent Levels, but the Blue Route also saves around £620m which Plaid Cymru would want to see reinvested in projects elsewhere in Wales.
– Plaid Cymru Economy spokesperson Rhun ap Iorwerth AM
We are giving the Labour government a chance to back out of its plans to borrow and spend £1bn on a 14km stretch of motorway; a totally disproportionate way of dealing with congestion.
Plaid Cymru’s alternative plan would be completed more quickly and would leave more money for the infrastructure needs of the valleys, west and north Wales.