Worried regional contractors have contacted the Enquirer to spell out the shift in tendering practices as the big boys try to muscle in on smaller contracts they would not have bothered with two years ago.

One regional boss told the Enquirer: “More and more major names are turning up on tender lists for jobs you would think are way to small for them.

“A shortage of work means they don’t mind a bit of bottom feeding but it’s a worry for local firms like us as they chase jobs as small as £5m.”

Smaller contractors fear the majors are bidding at wafer thin margins just to win work and keep turnover ticking over.

But one insolvency expert told the Enquirer: “It’s never a good thing for anyone when bigger firms are forced to chase smaller contracts.

“They often win work at low margins which is ruinous in the long run while the smaller firms get squeezed out.”

The shift comes as regional contractors confirmed how precarious the fledgling construction revival is.

Douglas Kell, regional director of the Civil Engineering Contractors Association (North East) said: “One or two firms may find things picking up for them. But that’s probably because they’re gathering work previously done by smaller contractors now insolvent as tender prices have been shaved beyond levels of safety.”

Another regional boss said: “A few years ago the majors were crowing about being on health and education frameworks but now all that public work has come to an end.

“Now it’s suddenly back to competitive tendering and they aren’t averse to winning work at ridiculous margins.

“The whole situation is storing up problems for the future and just isn’t sustainable.”