The Australian construction firm behind the redevelopment of Wembley stadim has admitted that its losses on the disaster-struck project have ballooned to just under £106 million - far higher than was originally feared.

Multiplex, which still has construction workers on site at the 90,000 seat stadium battling to finishing the beleaguered development, said today that its involvement in rebuilding the new home for English football has "significantly and adversely" affected its profits.

After initially setting out a worst-case calculation late last year that its losses on Wembley could reach £87 million, Multiplex has now had to increase that figure by more than a fifth to A$250.7 million (£105.8 million).

The firm's Wembley losses helped push it into an overall after-tax loss of more than £50 million. Multiplex has also been hit by its involvement in the Global Switch building regeneration project taking place in Stratford, East London.

Both UK projects have become blots on an otherwise extremely successful domestic construction portfolio operated by the Australian group.

As well as being hit by delays to the timetable for Wembley, Multiplex suffered a soaring increase in raw materials costs and damaging spats with sub-contractors on site.

A series of high-profile setbacks ahead of a hoped-for handover in time for the FA Cup Final in May eventually prompted football's governing body to abandon the idea of staging the event at Wembley earlier this week.

Instead, and to the consternation of legions on England fans, it has moved the game to the Millennium Stadium in Cardiff. Other events, including rock concerts featuring artists such as Bon Jovi, may also have to be moved.

The FA said it needed Multiplex to be 100 per cent certain it could complete the Wembley project on time. The Australian company was only able to express a 70 per cent likelihood that it could meet the commitment.

However, Multiplex is hoping that today's losses will draw a line under its traumatic assocation with the stadium. The figure includes a fine of £120,000 a day for delays to the handover process and should see the losses capped at this level.

It said today that "nothing has changed" since it expressed that hope that it could finish the stadium in May. It also insisted that Wembley would pose no dangerous threat to its financial well-being and stuck to its guidance on profits for the full year.

"The UK construction division also has a solid workbook in hand and the emphasis will be on the successful delivery of existing opportunities over the next two years rather than necessarily growing the workbook," it added.

Multiplex agreed a fixed-price contract of £445m to build Wembley Stadium - although the project will cost the Football Association a total of £757m.

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