An adjudicator ruled in favour of Hyder in May but his decision was challenged by Carillion.

Mr Justice Edwards-Stuart ruled on the case and his judgement was published today stating that Carillion’s challenge had failed and the firm must pay Hyder £3.1m plus interest and 50% of the adjudicator’s fees.

The row erupted over consultancy work on the £250m rail improvement job in 2009.

Hyder’s fee was determined by a complicated incentive structure which led to the massive disparity in figures between both sides.