International support services and construction group Interserve has warned that it expected the out-turn for the year to be significantly below previous forecasts.
It said trading in the UK in July and August was disappointing, particularly in support services, but also in the construction division.
An update said: "Further progress continues to be made on contracts within our exited Energy from Waste business.
"However, the anticipated timing and complexities of completion mean that the Board now considers it likely that the final costs will significantly exceed the £160m currently provided."
Interserve said a further update would be provided in due course.
Interserve said the board continues to believe that the group would be able to operate within its banking covenants for the year ended 31 December.