The decision by Transport Infrastructure Ireland (TII) to move the speed limit sign at Redmondstown, near Clonmel, has been criticised as "stupid".
Cllr.Martin Lonergan made his remarks at a meeting of Clonmel Borough District.
District Engineer Eamon Lonergan said he had contacted TII about this, while the Medite company had also expressed concern.
He said that TII implemented speed limits in respect of guidelines but a problem had presented itself and it was up to TII to resolve this.
Cllr.Siobhan Ambrose said that the speed limit had been raised from 60-100 kilometres per hour, and the moving of the sign had caused huge problems. People living nearby were very concerned.
Cllr. Michael Murphy said a very dangerous situation had been created at Redmondstown.