Balfour Beatty has pledged to continue its pursuit of Mowlem, despite it looking increasingly likely that Carillion will get in first.

A spokesperson for Balfour said the contractor had not yet conceded defeat.

The spokesperson said: “We are still considering what we’re going to do. There will be a point where we’ll have to put up or shut up. At the moment we’re evaluating what we’ve found in due diligence.”

It is understood that shareholders owning 29% of Mowlem’s shares have given undertakings to sell their shares to Carillion. Balfour has been in talks with Mowlem since Carillion approached it in November. It is thought to be putting together a cash deal worth between 218p and 222p a share.

A bid at the top of that range would value Mowlem at £315m, a 9% premium on Carillion’s original offer, currently worth about 205p a share.