The move is the latest twist in a long-running payment dispute between the specialist and ISG.

Earlier this year FK won a High Court ruling enforcing an adjudication requiring ISG to pay its subcontractor £1.69m.

ISG challenged the adjudicator’s award relating to Project Barberry, a warehouse project at an industrial park in Avonmouth Docks.

The payment dispute over the £3.4m cladding subcontract arose when FK issued a £1.69m application for payment which was greeted with a payless notice and then not paid.

An adjudicator ruled in FK’s favour in February directing ISG to pay the application. The payment was not released which led FK to seek enforcement of the ruling in the High Court.

But a ruling in the Technology and Construction Court this week has reversed that decision on a technicality and told FK to hand back the £1.69m.

The situation is further complicated by the fact that FK and ISG have a number of payment disputes ongoing including another warehouse project that was built at the London Gateway project in Essex.

The Enquirer understands that FK is attempting to negotiate an overall settlement with ISG but has not been able to progress discussions.

An FK spokesperson said: FK are disappointed in the result but this will not effect its trading position and are keen to resolve the final accounts that will result in no repayment to ISG.”