The Competition Appeal Tribunal hearing starting today is the latest round in a long running battle between the OFT and contractors over the size of fines levied against them.

Court documents seen by the Enquirer list a series of appeals by contractors including Quarmby Construction, Ballast Needham, Durkan, Sol, Bowmer & Kirkland and Galliford Try.

Oral evidence will start to be heard this week before a three-man panel makes a judgement on each individual case later in the year during hearings lasting up to two days each.

Kier is the first contractor to make its case and the firm will claim the £18m fine levied against it was excessive.