A group of business leaders has called for the proposed high-speed rail link between London and Birmingham to be scrapped.
In an open letter, the group calls the plan an "expensive white elephant", and a "vanity project".
The Transport Secretary Philip Hammond insisted the £17bn project would deliver major strategic benefits to the economy.
Work on the line is due to start in 2015, if the route is approved.
A public consultation began last month on the proposed location of the new track in the Chilterns, Buckinghamshire and Warwickshire.
Expensive 'train set'The project, known as HS2, is designed to shorten journey times between London and Birmingham, before connecting to Manchester and Leeds.
In total, it will cost an estimated £32bn.
But the letter to the Daily Telegraph says "an extremely expensive white elephant isn't what the economy needs".
"If the government want to encourage growth", it says, "there are better ways to get Britain growing and make us more competitive than getting each family to pay over £1,000 for a vanity project that we cannot afford."
The letter is signed by 21 business leaders, politicians and economists including the former Chancellor, Lord Lawson, and Lord Wolfson, the chief executive of Next.
It dismisses HS2 as a "train set" which will be used only by a minority.
"There are better options to increase capacity more affordably and reduce overcrowding more quickly than HS2, which will take decades to complete," argues the letter.
"Stretched commuter trains and congested roads are a bigger issue than the journey time to London."