The cost of the HS2 high-speed railway line has risen by another £1.7 billion over the past year as the pandemic and social distancing measures forced delays and reduced productivity on Britain’s biggest infrastructure project.
The costs associated with the first phase of the high-speed link between London and Birmingham have increased by as much as £800 million.
That is on top of an £800 million increase in costs previously announced by HS2 in October.
The cost of the Birmingham Interchange has also been hit by a further £100 million increase to £370 million, before contractors have been appointed.
The £1.7 billion increase marks a further significant uplift on the project’s £106 billion budget.
One contractor linked to the project said that HS2 Ltd, the state-funded body responsible for delivering the railway line, “still doesn’t really know how much Covid has added”.
The increase comes during a growing backlash to HS2, which was seen as one of the reasons behind the Conservatives’ crushing loss to the Liberal Democrats in the Chesham & Amersham by-election.
The new line is due to run through the Buckinghamshire constituency.
The spending is still within the £40.3 billion scope set for phase 1 but the project is already drawing on its contingency budget of £4.3 billion only a year after building on the line was given the go-ahead by Boris Johnson.
The cost is expected to increase further as budgets for key parts of the project have not yet been agreed.
A National Audit Office report last year warned that planning on the railway is at such early stages that it is almost impossible to predict the final costs.
Government officials conceded there had been “unavoidable costs” arising from the pandemic.
The Department for Transport added: “Our focus remains on controlling costs, to ensure this ambitious new railway delivers its wealth of benefits at value for money for the taxpayer. The response to Covid-19 remains ongoing and final assessments of its effect have not been made.”