Costs for main civil works on the government's controversial High Speed 2 (HS2) project are coming in £1bn over budget.
HS2 currently has a target for construction costs of £6.6bn, while its overall budget for the project is £56bn.
The New Civil Engineer has reported that interim costs submitted by contractors are currently above the target price by about £1.2bn, with some being told to re-evaluate costs and report back to HS2 with reduced figures.
If the contractors come in at £6.6bn or under HS2 will share the savings with them.
Contractors include Skanska, Balfour Beatty and Kier.
HS2, which is currently in the design period, will link London to the West Midlands in its first phase while the second phase will connect the West Midlands to Crewe. The overall cost of HS2 is expected to come in at about £56bn, up from an initial cost of £32.7bn in 2010.
An HS2 spokesperson said: “We remain on track, and within our original cost package.”
Last month City A.M. reported that the actual monthly costs for the controversial project were buried in the government's transparency data due to an accounting anomaly that one pressure group called "nonsensical".
The total monthly cost of contingent labour, classified as agency (clerical and admin) staff, interim managers and specialist contractors for HS2 in February comes in at -£740,766.97.
However, HS2 refused to give the actual figure of what the department had spent on contingent labour costs.