Demand for the HS2 high-speed rail project has "likely been overestimated", according to a report by a think-tank.
Evidence HS2 will promote economic growth or tackle the north-south divide is "limited", the report - from the New Economics Foundation - claims.
HS2 will reduce the average journey time from central Leeds to London from 2 hours 20 minutes to 1 hour 28 minutes.
The report adds the line will be "carbon intensive and environmentally damaging".
In January 2012 the construction of phase 1 between London and Birmingham was approved. Construction is set to begin in 2017 with an indicated opening date of 2026.
More top news
Weather: late forecast with Kerry Gosney
A new lead has emerged in the case of Ben Needham after "Calendar" helped one of Greece's biggest TV shows.
Prince Charles, Russell Brand and vlogger Zoella have been named in the annual Debrett's 500 list of the most influential Brits today.