Shares in aerospace electronics group Cobham have fallen sharply after it said sales had been hit by delays to the awarding of US defence contracts.
The company said the delays also left it uncertain about its growth prospects for the fourth quarter.
Cobham makes equipment that helps military vehicles and aircraft to communicate.
The firm's shares fell by 10% at one stage, before recovering slightly to stand down nearly 8%.
A company statement added: "Organic revenue in the technology divisions was slightly down on the first nine months of 2009, and it is now unlikely that a significant increase in organic revenue growth for the full year will be achieved."
Cobham added that the recently announced UK National Security Strategy and Strategic Defence and Security Review, with its emphasis on the use of technology, had helped to give the board confidence for progress over the medium term.