A number of UK regions have been revealed as losing out if HS2 - the high-speed rail link between London and northern cities - is built.
A document released under the Freedom of Information Act and reported on by BBC Newsnight has revealed that places including Aberdeen, Cardiff and Norfolk could see hundreds of millions of pounds wiped from their annual economic output.
The research, by KPMG accountants, suggests 50 places could be worse off.
The bill intended to give Prime Minister David Cameron the power to build and operate HS2 will be presented to Parliament in November and debated throughout next year.
The £17 billion project faces opposition from MPs with constituencies along the track's route, because of environmental concerns. The Government claims the proposed track will spread prosperity around the country, by cutting journey times between London and northern cities.
The report said the lines - which would connect London to Birmingham and to Manchester and Leeds - could boost the UK economy by £15 billion a year. It also said Greater London stood to benefit to the tune of £2.8 billion, and the West Midlands £1.5 billion.
The original 92-page document neglected to mention the areas which weren't on the line and stood to lose out.
James Bream, policy director of Aberdeen's Chamber of Commerce, told the BBC it was "really disappointing" that the effects were left out of the original report.
A spokesman for the Department for Transport said: "These figures show it boosts the north overall more than the south.
"Of course the line does not serve every city and region and these figures reflect that."
According to the research, the worst affected places would be (estimated loss to GDP in brackets):
Aberdeenshire, Aberdeen City and Moray (£220m)
Norfolk East (£164m)
Dundee and Angus (£96m)
Norfolk West (£56m)