Vital parts of HS2 need to be saved to boost connections across the North, peers were told tonight.
Plans for the high-speed railway linking London and Birmingham, and Manchester and Leeds could be scrapped, curbed or cut back under a Government review into the project.
Latest estimates suggest the scheme could cost £106billion, dwarfing the official £56billion price tag for the 250mph line.
Labour peer Lord Berkeley, who was deputy chairman of a Government-ordered study into the project, has disowned the conclusions of a draft review by former HS2 chairman Douglas Oakervee and “was not given an opportunity to amend it”.
The Government could reveal the findings and make a final decision within days.
A separate study by rail expert Keith Williams is examining the wider industry, including the franchising system.
Supporters and northern leaders want HS2 to go ahead as planned, with boosted rail links across the region under a separate scheme dubbed HS3 or Northern Powerhouse Rail.
The project would connect the North’s six big cities - Newcastle, Leeds, Hull, Sheffield, Manchester and Liverpool and Manchester Airport.
Grilled by the House of Lords Economic Affairs Committee about possible threats to HS2, Lord Berkeley said tonight: “The parts of HS2 within what you might call the Northern Powerhouse area - from Crewe to Manchester and around Leeds and Sheffield - they need to be retained as part of a local network.
He added: “Cancelling those would be counter-productive for the region.”
Transport chiefs have also faced calls to switch construction of HS2 so it begins in the North and works down to London.
Under current plans, the line between Birmingham and the capital would open in 2029.
The sections between Birmingham and Leeds and Manchester are expected to open in 2032-33.
But Lord Berkeley suggested homeowners in the well-heeled South would object if the railway was built from the North down - one plan investigated by the review.
“If you’re going to start in the North the consequence is you do the southern bit last, which means that the people around that area are going to be suffering 10 years of blight,” he said.
“I don’t think anybody would want to wish 10 years of blight on the people of Buckinghamshire.”
Railway Industry Association chief executive Darren Caplan backed Lord Berkeley’s call for boosted links in the North.
He said: “The Railway Industry Association and its members believe both HS2 and improvements to the current network are needed, it is not one or the other.
“HS2 will bring a transformational upgrade in capacity and connectivity, benefiting towns and communities across the UK, whilst we also need to invest in the traditional network, maintaining and building a world-class railway in every part of the country, whether intercity, commuter, or regional and rural lines.
“So we urge both the forthcoming Oakervee and Williams Rail Reviews to fully support both HS2 and other major rail enhancement projects, and herald a new golden age for the railways in the years ahead.”