The government will take back control of rail spending budgets as a result of Darling's rail review.
The move follows a row between transport ministers and former rail regulator Tom Winsor over the setting of rail budgets.
Last December Winsor used his powers to grant a spending budget which was £11bn more than anticipated by ministers.
The White Paper says that in future, the government will ask the regulator to price five year spending programmes set out by the government.
If the regulator says programmes will be more expensive than the government expects, ministers will be allowed to scale down spending proposals to meet budget limits agreed with the Treasury.
'Under this process the independent economic regulator retains the full and sole authority to price the outputs Network Rail is to provide, and government has the ability to decide how much expenditure is to be devoted to the railway, ' says the White Paper.