High Court hearing between client and the Wembley client will commence early next month

Wembley contractor Multiplex will make its first court appearance in the case against client Wembley National Stadium Limited next month

The High Court hearing, in the first week of October, will be the first time the increasingly bitter dispute has reached the courts.

WNSL will use the hearing to challenge an adjudication ruling made earlier this month, that determined it had to pay Multiplex £17m.

The escalation of the legal dispute follows a series of adjudications between the two parties, which have so far ruled that Multiplex is owed £22m by WNSL.

This includes the £17m figure, which WNSL withheld from Multiplex’s monthly payments. An adjudicator ruled that WNSL should have taken the sum out of a bond that covers the project, and so must pay the money to Multiplex.

Relations between the client and contractor have plummeted over the past two months, with each side making a series of public statements blaming the other for delays.

Multiplex says that the stadium is unlikely to host crucial test events before next June as a result of delays on WNSL’s commissioning works.

The court hearing, which is likely to be the first stage in a £320m legal battle, will make WNSL the third organisation to face Multiplex in court over the beleaguered stadium, which still may not be finished in time for next year’s FA Cup final.

In June, the Australian contractor won a £50m court battle against its former steelwork subcontractor, Cleveland Bridge, and it has also had a preliminary court meeting with M&E firm Honeywell in order to challenge a ruling that the subcontractor was not bound by a completion date.

It is understood that Multiplex is also about to launch adjudication proceedings against Mott MacDonald, the engineering consultant on the stadium. Mott MacDonald is at the centre of a dispute over design changes on the scheme, and was repeatedly attacked by Multiplex witnesses in the Cleveland Bridge trial.