Road tolling was a key topic discussed at a fringe seminar hosted by the Chartered Institute of Logistics and Transport at this week's Conservative Party Conference in Manchester.

Director of the RAC Foundation, Prof Stephen Glaister, told delegates that the Treasury faces a £30m per year deficit from falling fuel duty by 2027, thanks to to advances in vehicle technology, coupled with a national debt that will cost the UK £70bn annually by 2017. "So the amount of money coming in is falling, which makes it hard to increase investment in roads."

He warned delegates that if government traffic forecasts were accurate, which predict around 40% more vehicles on roads by 2040, then congestion will have to be managed and "we are going to have to introduce distance-based charging".

Road tolling, or the ‘user pays principle’, was widely accepted by delegates as an inevitability on UK roads, however, where and how it was implemented would be pivotal to its success.

One concern was the affect of tolling only a single road, as motorists would often switch routes to a neighbouring road to avoid a charge. Instead, the idea of tolling a network of roads was mooted, as was the notion of paying different levels of road fund licence according to the roads you want to use.

FTA chief executive Theo de Pencier told that he believes charging will be considered in the future, but that it would be difficult for any one political party to introduce: "The Labour Party floated ideas and got a slap across the chops for their pains if you like, which has clearly put off the current government from even discussing it. It is the elephant in the room."

"From our perspective, charging to use the roads, if offset against something like fuel duty, for example, we would want to seriously consider it, as we think there is a much stronger chance of continuous and the right level of investment in maintaining our infrastructure," he added.