Protestors against a new road in north east Wales say it would do "untold damage" to ancient woodland and natural habitats.
A petition against the Flintshire Corridor scheme has been signed by almost 1,500 people.
The National Assembly's petitions committee has agreed to look at the issue in more detail in the autumn.
The Welsh Government said the project "will reduce traffic congestion and carbon emissions".
The proposed "red route" would run between the Flintshire Bridge and a new interchange on the A55 at Northop.
"Clearly the decision to choose the red route took place before the Welsh Government were fully aware of the pending climate emergency," the petition co-ordinator and climate scientist Tom Rippeth said.
He said the First Minister Mark Drakeford's rejection of the M4 relief road south of Newport "shows a clear change in government policy away from building road in environmentally sensitive areas" and that "his government's support for the red route must also be cancelled".
A spokesman for the Welsh Government said they have taken full account of the technical, social, economic and environmental aspects of the Flintshire Corridor scheme.
"The red route will reduce traffic congestion and carbon emissions, which will improve air quality for people living in the area.
"Whilst the red option crosses the Lead Brook valley and its ancient woodland, the crossing location has been selected at a point where the steep-sided valley can be spanned by a viaduct with minimum effect on the watercourse and vegetation.
"The red route is a huge development in north east Wales and will protect the regional economy," he said.