Transport secretary Mark Harper has confirmed construction of certain parts of HS2 will be delayed to save money.
Sections from Manchester to Crewe and Birmingham to Crewe will be pushed out until the middle of the next decade, he said.
The high-speed railway will link London, the Midlands and North of England, but costs have soared recently.
. In 2010, it was estimated to cost around £33bn but that has since swollen to at least £71bn.
“We have seen significant inflationary pressure and increased project costs,” Harper said.
“We will rephase construction by two years, with an aim to deliver high-speed services to Crewe and the north-west as soon as possible”.
Harper confirmed over £20bn had already been spent on the first stage of the project, building the link between Old Oak Common in London and Curzon Street in Birmingham.
“We remain committed to delivering HS2 services to Euston, and will address affordability pressures to ensure the overall spending profile is manageable,” he added.
Mark Thurston, chief executive of HS2 Ltd, recently told the BBC that he and the government were examining the phasing of the build and the timing.
The project is grappling with the rising cost of materials due to the high rate of inflation.
Thurston said the impact of inflation had been "significant" in the past year, "whether that's in timber, steel, aggregates for all the concrete we need to use to build the job, labour, all our energy costs, fuel".
Road projects in Kent, Liverpool and travel budgets are also being scaled back, Harper said.
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