The multi-consultancy and construction services group saw revenue jump over 50% to £1.22bn, while pre-tax losses doubled to £81m in the year to April 2023, after £74m in interest payments.

EBITDA,  before exceptional non- recurring costs, increased to £83m (2022 £59m), while cash generated doubled to £75m.

RSK founder and CEO Alan Ryder said the group, established in 1989, was on track to achieve £5bn revenue by 2030.

Since year-end, he said the business has completed a further 24 acquisition

Ryder said: “The combination of organic growth in several business units the full-year effect of acquisitions completed in the previous period and the continuation of our acquisition programme has resulted in turnover exceeding £1bn for the first time in the group’s history.

“We have become a global leader in our field and have the acquisition and banking facilities provided by Ares and NatWest Bank to support further growth and diversification this year.”

He added: “The board has also begun the process of identifying the best financial structure to support the delivery of our strategy to 2030.”

The business now employs 10,530 staff.