31 October 2013
Last updated at 01:11 ET
The cost of the HS2 project is now estimated at more than £40bn
MPs will vote later on whether to let the government start spending money on preparations for the HS2 rail project.
Money released by the vote would pay for surveys, buying property and compensating evicted residents.
Some Conservatives are expected to vote against the plans amid continued uncertainty over Labour’s support.
In June the government revised the estimated cost of building the high-speed link between London and the North of England from £32.7bn to £42.6bn.
HS2 would see lines built between Birmingham and London, followed by a V-shaped second phase building separate tracks from Birmingham to Manchester and Leeds.
‘No blank cheque’
Labour first proposed HS2 and says it still supports the principle, but shadow chancellor Ed Balls said last month that the coalition had “mismanaged” the scheme.
He said the costs had “shot up to £50bn” and warned there would be “no blank cheque” for HS2 if he was chancellor.
On Wednesday David Cameron said Labour was “too weak” to make a decision on HS2.
The Liberal Democrats back the project although on Wednesday aides of Nick Clegg denied supporting it was a “rail line” in any possible future coalition negotiations with the Labour party despite earlier comments made by Mr Clegg.
Earlier the Lib Dem leader had been asked if he would able to compromise on HS2 in any future government and he replied: “No. I was up in Sheffield yesterday talking to business leaders and they are absolutely appalled at the way in which Labour appears to be betraying the North.”
BBC deputy political editor James Landale said: “The politics are confused, the costs astronomic and the arguments disputed.
“But one thing is certain – the process of getting plans for a new high speed rail line through Parliament is going to take a very long time.”
He said “crunch time” would come next spring when a second bill comes before Parliament, asking MPs to grant the government power to seize land to build the line.
Running in 2026?
A government report published on Tuesday slightly lowered the predicted benefits of HS2 compared with the costs.
The expected “benefit-cost ratio” was reduced from £2.50 to £2.30 in benefits for every pound spent.
This was mostly due to the increase in the total expected cost earlier this year.
At present the government hopes to begin construction on the first phase of HS2 in 2017 and open that part of the line in 2026.
The additional lines to Leeds and Manchester could then be completed by 2032-33.