Directors have offered to redeploy staff in Australia where the group is expanding on the back of piling demand from ports and mining projects.

So far several key staff have jumped at the opportunity and more are expected to follow.

In recent years the UK business has shrunk compared to the rest of the group as workloads fell and Keller expanded internationally.

Staff numbers are down to 400 from around 600 before the recession hit.

In the last six months the UK side failed to break into the black again with losses of £100,000 compared to a loss of  £400,000 during the first half of 2009.

Sales dipped 8% to £28.1m, meaning the UK now accounts for  less than 6% of total group turnover.

Chairman Roy Franklin said: “The UK market remains very challenging and our UK business has been further downsized to reflect this.

“Where possible, skilled people are being considered for transfer to other parts of the group, such as Australia, where demand remains high.”

Keller’s main job in this country is a piling contract for Crossrail at London’s Tottenham Court Road station.

Across the group falling demand and tough competition in the US, where it is market leader, saw half-year pre-tax profits plummet nearly three quarters to £11.3m. Sales also slid to £497m from £553m last time.

Group margins now stand at 2.8% compared to 7.7% in the comparable period in 2009.

Around a third of Keller’s revenue now comes from Australia and other developing markets.

“The first half has been a challenging period for the Group particularly in the US, where the construction market continued to deteriorate.

“However, we have been encouraged by the progress made in our developing markets, where we have continued our success of recent years in profitably growing our business.

“This demonstrates the benefit of our strategy of geographic diversification, to which we remain fully committed.”

In Australia demand for resources from China and the rest of Asia is fueling development.

Australian revenue rose to £80.7m (2009: £62.8m) and operating profit reached £8m, compared to £6.2m in the first half last year.   On a constant currency basis, both revenue and operating profit were up 5% on last year.