The Transport Select Committee has not received key evaluation reports on ‘smart motorways' as part of its inquiry into the controversial roads, as publication is being held up in the Department for Transport (DfT).

As Highways has reported, the government-owned company has produced two post opening project evaluation (POPE) reports – a five-years-after opening report covering junctions 10 to 13 of the M1 and a one-year-after report covering junctions 28 to 31 and 32 to 35a.

Baronness Vere appears to have called in the reports, requiring them to receive ministerial clearance before publication. Such a clearance procedure does not have to happen with the release of Highways England POPE reports, but is the prerogative of the minister.

The existence of the unpublished documents was revealed by Highways following a request under the Freedom of Information Act. In early May Highways England refused to release them, claiming that they were in draft form and were due to be published in June. This did not happen.

Huw Merriman MP, chair of the Transport Select Committee, put down a parliamentary question about the reports amid concern that the Government was seeking to conceal the data in the report until the committee completes its current inquiry into smart motorways.

In a recent letter Highways England's acting chief executive, Nick Harris, told Mr Merriman: ‘I will ensure that these reports are available to the Committee as soon as they are published.'

However, in a review of Highways' Freedom of Information request, Highways England has now disclosed that 'Ministerial clearance has been requested prior to HE's release of these reports [which] are currently with the private office of the Roads Minister.'

During a hearing of the inquiry three weeks ago, road minister Baroness Vere (pictured) made it very clear that she had the reports and had read them. She pledged to send the reports to the committee herself: ‘Obviously, I will write to you, Chair, with the POPE reports, which I think you will find interesting.'

Mr Merriman asked the minister: ‘Can I press you for a date, not least because we are intending to get our report out before Parliament breaks for the summer recess?'

Baroness Vere said: ‘I hope to get them to you the week after next.' According to that timetable, the reports should have been disclosed to the committee by the end of last week.

On Monday, a spokesperson for the DfT confirmed that Baroness Vere has the reports and said they would be sent to the committee 'shortly'.

At the time of writing, Highways England has not published the reports on its publications page.

The scheme between junctions 10 and 13 opened in December 2012 and a one-year after POPE report was completed in 2016 but not published until January 2020, more than three years later.

The section between junctions 28 and 31 opened in 2016 and the junctions 32-35a scheme opened the following spring.