The authorities will look again at whether forcing motorway service areas (MSAs) to display their fuel prices would result in lower prices for motorists.

The decision was revealed in a letter to the transport secretary Chris Grayling from Andrea Coscelli, chief executive of the Competition and Markets Authority (CMA).

Coscelli pointed out that the OFT had carried out an inquiry into fuel pricing in 2013, and found there were legitimate reasons for the higher prices at MSAs.

A trial run by Highways England at five MSAs concluded there was no overall effect on prices.