South Northamptonshire MP Andrea Leadsom called an urgent review of the business case for HS2, which she described as 'one of the single biggest concerns for her constituents'.
In her first debate as a backbencher since quitting as Leader of the Commons, Mrs Leadsom claimed the bill for the controversial high-speed rail line could surpass £100 billion.
“There is no doubt that investment in infrastructure is the key to solving the UK’s productivity challenge, and we have to see investment that benefits our entire United Kingdom," she said afterwards.
“Getting the best value for money has to be at the heart of all that we do, and it is vital that we make sure we are investing in the right infrastructure projects.
“HS2 is one of the single biggest concerns for my constituents, and over the years it has become clear there are significant questions about value for money for the taxpayer.
“I’m calling on the Government to carry out a full reassessment of the business case for HS2.”
In Westminster Hall, Mrs Leadsom called for the Government to commit to a full review of the business case for HS2 before the 'notice to proceed' is granted later this year.
She felt it was important that HS2 was one of the first issues she raised in Parliament on behalf of her constituents, and wanted to put on record her strong concerns about the business case and value for taxpayer money.
Victoria Prentis, the Conservative MP for Banbury, said she 'does not feel that £100bn is worth some jobs in Birmingham'.
"I think there may be other ways in assisting with employment. HS2 is a white elephant that is trampling over the dreams and aspirations of my constituents and I cannot support it," she added.
Transport minister Nusrat Ghani defended the scheme, saying she believed the current HS2 cost estimate of just over £55bn is accurate, and that the scheme is vital to 'keeping the country moving'.
"We have an overused and overcrowded railway, which is also one of the oldest," she said.
"With HS2 in place, we can deal with the pressures on express trains, freight trains and slower local commuter services, which are already operating at peak capacity.
"That is just one of the reasons why HS2 is crucial: to solve our chronic capacity problems."