Defence technology firm Qinetiq today warned full-year results were “unlikely” to match previous hopes after contract delays in key US and UK markets.

The firm said President Obama’s drawn-out decision over policy in Afghanistan and “political and economic” delays to UK awards had caused short-term uncertainties.

Shares in Qinetiq – which had risen sharply since the appointment of new chief executive Leo Quinn earlier this month – fell more than 7% on the news.

The company said there was “more limited visibility” about second-half orders in its UK-focused Europe, Middle East and Africa (EMEA) division, which is usually boosted by a large number of short-term deals.

It added: “Given the risks around closing pending orders in the US, and achieving the normal pattern of contract wins in UK, the board considers that it is unlikely to achieve its previous expectations.”

Investec analyst Chris Dyett said: “Ministry of Defence contract delays due to intense budgetary pressures and political wrangling is impacting the EMEA business.”

The company makes equipment such as the handheld EARS system used to detect enemy snipers – as well as the Dragonrunner reconnaissance robot used in urban warfare and Talon bomb disposal robots.

The group’s underlying revenues for the six months to September 30 were 1% lower at £806.3m, with pre-tax profits off 2% at £45.1m.

Mr Dyett added: “Half year numbers were modestly ahead of our forecasts, but continuing delays in defence contract awards both in the US and UK will lead us to downgrade 2010 and 2011 estimates by around 15%.”

Qinetiq – the former Defence Evaluation and Research Agency – can trace its heritage from the birth of powered flight in the UK at Farnborough through the development of radar during the Second World War.

The company has sites across the UK, at locations including Salisbury in Wiltshire, Portsmouth, Plymouth, Glasgow and Christchurch, Dorset.