In a statement outlining the opposition's current road transport policy, shadow transport secretary Maria Eagle MP says ministers must "stop being dogmatic" and examine evidence from the Department for Transport (DfT) that the move towards 14.6m and 15.65m trailers could lead to more cyclist casualties.
She adds that Labour would use money from the proposed lorry road user charge to help hauliers improve their driver training and awareness.
Labour would use the cash to equip trucks with under-run protection to avoid cyclists falling under HGV wheels, as well as blind spot mirrors.
Eagle accepts that many road transport companies have already proactively carried out these measures.
She says: "The decision to allow longer heavy goods vehicles should be reversed and the £23m annual income from the planned HGV road charging scheme hypothecated to work with the road haulage industry on equipping lorries with safety equipment, such as side under-run protection and blind spot mirrors."