Atkins spent $7.3mn on Parsons Brinckerhoff bid
Balfour Beatty unit was eventually sold to WSP in a deal worth $1.24bn
Although the company did not name Parsons Brinckerhoff directly, the firm did say that it "incurred around £4.5mn of external fees in relation to the unsuccessful pursuit of a significant acquisition opportunity".
Atkins and WSP were both in the running to buy Parsons Brinckerhoff alongside a number of private equity bidders. WSP eventually won out on 4 September when it announced it had agreed a $1.24bn deal for the unit.
The company said that the expenses incurred in the six months to 30 September will be treated as an exceptional cost.
It added that its Middle East business enjoyed a strong first half of the year as it began with the mobilisation and design delivery of a number of metro projects.
"This is expected to contribute to a significant year on year performance improvement for the region," the company said in a statement to the London Stock Exchange.
"The group's financial position remains strong, supported by our continued focus on cash generation across the business."
Parsons Brinckerhoff is a specialist in transportation engineering projects and is involved in a number of big-ticket projects in the region, including the Saudi Landbridge rail project alongside Fluor and the Makkah Metro.