The National Audit Office (NAO) has urged caution regarding the revised plans for the HS2 high-speed rail project, stating that work should not proceed until there is clear confidence that the updated proposals are achievable. The watchdog emphasized the need to establish a stable foundation to prevent a recurrence of previous setbacks in the initiative.

In a report released this week, the NAO highlighted concerns over the project’s management and delivery timeline. The Department for Transport (DfT) and HS2 Ltd are currently working toward a comprehensive reset of the programme, expected to conclude by spring 2027. This reset aims to produce a detailed plan for the remaining construction phases and bring the project under better control.

This comes after Transport Secretary Heidi Alexander announced last month that HS2’s estimated costs have increased and the timeline extended, prompting HS2 Ltd CEO Mark Wild to initiate a formal review and adjustment process. The NAO stressed that it was vital for the DfT and HS2 Ltd to complete this reset accurately to avoid repeating prior difficulties related to delays and budget overruns.

The report specifically called on the responsible bodies to avoid implementing any revised plans until they are fully confident that all factors required to ensure successful delivery are in place. The watchdog’s recommendation aims to strengthen governance and oversight in hopes of achieving more predictable progress going forward.

Responding to the NAO’s comments, a spokesperson for HS2 Ltd acknowledged the challenges faced so far, noting that the fundamental reset was necessary to regain control of the programme. The statement said the initiative was intended to “break the cycle of poor delivery, delays and cost increases” that have previously hampered the project.

HS2, intended to connect London with major cities in the Midlands and Northern England through a new high-speed rail line, remains one of the UK’s largest and most complex infrastructure undertakings. The latest developments underscore ongoing scrutiny over its budget, timeline, and overall feasibility as stakeholders seek to balance ambition with practical delivery constraints.