Operating profit for the six months to September was down 20.4% in the UK to £24.6m as turnover dropped to £420.4m from £454.7m.

Globally the picture was brighter with group turnover up 26.9% to £842.9m as operating profit grew 8.8% to £49.3m.

Atkins said the fall in UK staff was mainly due to the number of people already put on redundancy notice at the year end with 237 people leaving during the last six months.

The consultant said: “As anticipated, the UK market remains challenging.

“The year on year revenue decrease reflects staffing reductions, the majority of which were completed by the end of the last financial year.

“Since 31 March 2011, we have seen underlying headcount stabilising, with the slight reduction in the six month period primarily reflecting those staff in our highways and transportation business already on notice of redundancy at the end of the last financial year.

“The overall outlook for the UK remains stable, with the business working in a number of well-funded markets.

“However, we see a challenging second half of the year for our rail business, due to the delays in signalling projects coming to the market.

“We have a solid, diversified platform to help navigate short term market challenges, and a breadth of expertise that will help us exploit opportunities when growth returns.”