A48 to close in both directions at Carmarthen after oil leak
Disruption is expected on the A48 in Carmarthenshire when the road is closed to fix a fractured pipeline.
Excavation work needs to be carried out to repair the pipe which has leaked thousands of litres of kerosene into a river near Nantycaws.
Rural Affairs Secretary Lesley Griffiths visited the site of the spill on Saturday.
In a letter to assembly members, she confirmed the scale of the spill was bigger than previously thought.
"It is estimated that around 140,000 litres of kerosene were spilled," she said, adding that "at this stage around two thirds of the spilt material has been recovered from the surface water."
Ms Griffiths also refuted a claim by Plaid Cymru AM Adam Price that the Welsh Government's response to the incident had been "sluggish"
Part of the eastbound carriageway is currently shut with the road due to close in both directions from 14-17 October.
Investigation work is currently underway to determine the cause and scale of the fracture.
Ms Griffiths told AMs: "In order to fix the fractured pipeline the road will need to be excavated across both carriageways."
This, she said, will require the "full closure of the A48 in both directions over the course of a weekend."
Jonathan Edwards, Carmarthen East and Dinefwr MP, said the closure would have "significant ramifications for the west Wales economy" and place a "huge burden" on residents along the diversion route.