Tractors and other farm machinery could be banned from using a major trunk road in Wales at peak travel times, forcing farmers and contractors to use alternative routes along narrow country lanes and villages.

The Welsh Government is considering restricting opportunities for vehicles that don’t achieve a minimum speed to travel on the A55, an 83-mile stretch of dual carriageway running between Holyhead and Chester.

“This would be at peak times of the day so that people who own or rent vehicles such as tractors don’t cause further delays and congestion to other motorists and only in areas with viable alternative routes,’’ a government spokesperson said.

Farmers and agricultural contractors say they will resist the proposals while farming unions are concerned that any ban could set a precedent for the roll-out of similar schemes on other trunk roads.

The government confirmed that its plan would need to pass legal scrutiny and that a consultation would be held in due course.

“We are committed to ensuring the A55 is fit for the 21st century for all road users and hope that those who regularly use the A55 take part in the consultation so nobody feels like they’re being excluded,’’ said the government spokesperson.

The Farmers’ Union of Wales holds regular meetings with North Wales police and says this issues has never been identified as a problem.

FUW Caernarfonshire senior county executive officer Gwynedd Watkin said agriculture employs thousands of people along the A55 corridor.

“I'd really like to see some evidence there is a genuine problem,’’ she said.

“If this goes ahead it could set a precedent for all other main roads and such a proposal should be rejected outright.’’

NFU Cymru is also deeply concerned about the precedent it could set.

Policy adviser Dafydd Jarrett said farmers will rightly be worried.

“We would be eager to learn what alternative arrangements are being proposed for farmers who use the A55 to access land in other areas of north Wales,’’ he said.

“Farming, like any other industry, needs to have good transport links and farmers must be able to access their land at all times of the day to ensure the welfare of their animals and smooth running of their business.”