Media playback is unsupported on your device Media caption Brexit secretary Stephen Barclay was questioned about HS2 by the BBC's Andrew Marr

A cabinet minister has told the BBC it is his gut feeling that the HS2 high-speed rail line will get the go-ahead.

Stephen Barclay told the BBC's Andrew Marr Show that the project was vital for "levelling up" the UK's transport network and improving capacity.

The Brexit secretary's comments come amid a row over the rising cost of the project, which could reach £106bn.

The first phase of the project is due to link London and Birmingham, followed by extensions to Leeds and Manchester.

Mr Barclay was asked by Andrew Marr for his "gut feeling" about whether the HS2 would be approved. "Yes", he replied firmly.

He said the government had given a "clear commitment to level up all parts of the United Kingdom... HS2 plays an important part in that".

That levelling up was not just about improving the speed of transport, but also improving capacity in the UK.

Mr Barclay stressed, though, that it was "important that we also get value for money".

Earlier this month, a leaked government-commissioned review suggested the total cost of HS2 could reach £106bn.

The findings of the independent review, conducted by former HS2 Ltd chair Doug Oakervee, have not yet been officially published. The Department for Transport has indicated it will be published soon.

Lord Berkeley, a vocal critic of HS2 who was deputy chairman of the Oakervee review before withdrawing his backing, published an independent assessment of the project.

He put the cost at at least £108bn, adding that the government should scrap the project to concentrate on improving the rail network in the north of England.

That drew criticism from northern political leaders and businesses, who said HS2 should be built in its entirety.

Whitehall's spending watchdog said last week that HS2 is over budget and behind schedule because its complexity and risks were under-estimated.

Image copyright Reuters Image caption HS2 has faced strong opposition from local communities

The National Audit Office (NAO) warned that it is impossible to "estimate with certainty what the final cost could be".

HS2 was allocated £56bn in 2015. Phase One between London and Birmingham was due to open in 2026, but full services are now forecast to start between 2031 and 2036.

Construction firms have warned that scrapping HS2 would cause major damage to the industry, while several environmental groups say going ahead with the project will have a huge impact on natural habitats and ancient woodland.

Image copyright Siemens/ PA Image caption A proposed design for an HS2 train

The Sunday Telegraph reported that former senior figures involved in HS2 have given signed statements to the prime minister's advisers, alleging the government-owned firm behind HS2 covered up spiralling costs on multiple occasions.

In a statement, HS2 responded: "Following the collapse of Carillion, HS2 Ltd recognised the need to engage a healthy industry while continuing to protect value for money for the taxpayer.

"Instead of artificially passing risk back and forth, as has happened on other publicly-funded projects, contractors who do not meet the required performance will lose a proportion of their fee.

"This incentivises good performance and also prevents windfall profits from public money."

The statement said that by revising the terms and conditions, "contractors have been able to reduce their prices and HS2 Ltd estimates £1bn of savings as a result".

By Peter Saull, BBC political reporter:

HS2 is the talk of Westminster at the moment. Will it get the go ahead or come off the rails? Or somewhere in between? Perhaps unsurprisingly, the government is at pains to avoid saying what might happen next.

Ministers don't want to pre-empt the findings of the Oakervee review, which despite a series of leaks, is yet to be officially published.

Steve Barclay has gone further than any of his Cabinet colleagues by revealing he has a hunch that the project will get the green light. But it's unclear how much insight he has.

While the Brexit secretary has a seat at the Cabinet table for now, he might not be there for too much longer. The Department for Exiting the EU will be wound up following the UK's departure this week.

Ultimately the decision on HS2 lies with Boris Johnson, in consultation with his chancellor and transport secretary.