Britain’s biggest contractor will also consider pulling out of some problem regions if they cannot promise a decent return.

Chief Executive Andrew McNaughton said there was a “high possibility” Balfour will be more selective in the projects it bids for.

He added: “We are assessing the risk of continuing to acquire new work in each building sector whilst current market conditions prevail”

Previous problems have been concentrated in the southern region.

The Enquirer understands that six of the 21 regional operating units are underperforming.

McNaughton said: “There are elements in the business that we are going to have to look quite hard at as to whether those are viable going forward.”

He said the bidding pipeline is “pretty robust” but “different in different regions so we are having to look carefully at each region where there are large variations.”

Balfour’s UK construction arm has a revenue of £2.5bn with regional work accounting for 50%, major projects for 40% and M&E 10%.

The regional divisions currently add around £100m a month to the overall work pipeline.

Balfour wants to make UK construction a “2% margin business” next year.

But McNaughton said: “Bits of that market may not be able to support a 2% business.”