More from: 'Bad debt sank Llewelyn Davies Yeang'
It is understood that the practice, ranked 13th in this year's AJ 100 list, has had to lay off staff - including one senior director - after it was told to 'stand down' on the £170 million Broomfield Hospital scheme.
The flagship PFI development for the Mid Essex Hospital Trust was put on hold just before financial close and is subject to a government review into healthcare provision in the east of England.
As a result, bidding consortium Bouygues UK was forced to stop work on the scheme - a decision which has hit 95-strong LDY hard.
The only other project on LDY's books which is expected to generate more fee income
is its Great Ormond Street Children's Hospital scheme.
The last few months have been tough for the practice, which welcomed eco-superstar Ken Yeang on board last year.
It was hoped Yeang's arrival would move LDY away from its historical focus on healthcare and masterplanning (AJ 23.06.05).
However, in recent weeks the London-based practice has missed out on the CAD$1 billion (£485 million), high-profile University of Calgary competition and a contest for an eco-tower in Mexico, and was earlier this year overlooked for a green, mixed-use tower scheme in south London.
Some observers have raised questions about how much time Yeang is able to give to LDY because of other commitments.
As well as the work he does for his practice T R Hamzah & Yeang International in Kuala Lumpur, Malaysian-born Yeang has also developed his own range of bioclimatic clothing.
However, LDY chief Steve Featherstone has denied there is a crisis at the firm. He said: 'One of the characteristics of having Yeang join the firm is that the shape of our workload includes a much higher percentage of international work, as well as greater diversification in the UK.
He added: 'Of the team [working on Broomfield Hospital] 80 to 90 per cent have been reallocated to projects in the UK, Istanbul, the Middle East and the Far East.
'This is the nature of PFI - and any experienced business knows it must plan for these possibilities.'
Llewelyn Davies Yeang forced to lay off staff as hospital scheme collapses