The firm’s share price dipped nearly 10% on the news despite a resilient performance in the core UK market.
Atkins said: “Our consultancy business in North America continues to experience weak market conditions, further impacted by a number of project delays as uncertainty increases ahead of the US presidential election in November.
“We do not expect an improvement in the trading environment during the remainder of this financial year and, as a result, we have taken action to further reduce headcount to reflect anticipated market demand.
“The Peter Brown construction management at risk business is now expecting to incur additional costs in the final close out of legacy contracts and it is anticipated that this, together with the volume shortfall in its current backlog previously noted, will lead to an increased loss for this business in the current year.
“The Middle East has seen delays in projects coming to market, constraining our anticipated headcount growth, and reaching client agreement on various contract variations.
“In addition, we continue to experience more onerous contract payment terms on some of our current government and infrastructure work.
“While the group’s geographic and sector diversification continues to provide resilience, the outlook for the group’s overall performance for the full year is slightly below previous expectations.”
Atkins will announce its half year results on November 15.