Pre-tax profits jumped by over a third to £50m from turnover up 29% to £1.37bn, driven by strong performances at the support services and equipment divisions.

UK construction also faired well contributing £8m to profits, up 8%, on turnover ahead 12% at £433m.

Chief Executive Adrian Ringrose said that construction demand was improving, but warned that margins remained tight at 1.9% as supply chain pressures fed through.

The construction arm’s forward order book jumped to £1.4bn from £1bn a year ago.

Ringrose said two-thirds of construction revenue now came from framework agreements and repeat clients.

He added that the strategy to combine investment, development and project management skills to finance and deliver commercial developments had delivered starts at the Haymarket development in central Edinburgh and the Co-op building scheme in Newcastle.

Interserve’s Middle East construction business saw a recovery in demand but failed to see profit growth, which slipped from £5.6m last time to £4.3m in the first half.

For the group as a whole, Ringrose said: “We have delivered strong organic growth, achieved through robust performances from our UK support services and construction businesses and excellent results in equipment services.

“Market conditions in international construction and support services continue to be highly competitive, although we are now starting to see signs of improving demand.”

“Our strong organic growth was complemented by the performance of our acquisitions. Initial Facilities traded in line with our expectations during the period and its integration is progressing smoothly.”