HS2 has been a controversial project since plans emerged more than 10 years ago.

Here are the key dates in the history of the project: - January 2009: Labour establishes HS2 Ltd to examine the case for a new high-speed rail line.

  • December 2010: A consultation on a route for HS2 from London to Birmingham, with a Y-shaped section to Manchester and Leeds, is published by the Conservative-Liberal Democrat coalition.
  • January 2012: Transport secretary Justine Greening announces the Government has decided to go ahead with the project, despite concerns over its cost and the environmental impact of construction.
  • November 2013: The High Speed Rail (London-West Midlands) Bill setting out the powers needed to build Phase 1 of HS2 between London and Birmingham is introduced to Parliament.
  • January 2014: The Supreme Court rejects outstanding appeals by opponents of the rail scheme.
  • June 2016: The National Audit Office warns HS2 is under financial strain and could be delayed by a year.
  • September 2016: Simon Kirby resigns as HS2 Ltd chief executive.
  • February 2017: The High Speed Rail (London-West Midlands) Bill achieves Royal Assent, enabling preparation work to begin.
  • July 2017: HS2 Ltd accepts it was a "serious error" to make £1.76 million of unauthorised redundancy payments to staff.
  • December 2018: Sir Terry Morgan resigns as chairman of HS2 Ltd amid criticism over his role as chairman of Crossrail, which is delayed and over budget.
  • August 2019: The Conservatives commission a review into whether and how HS2 should continue. It will be led by former HS2 Ltd chairman Douglas Oakervee, with long-term critic of the project Lord Berkeley acting as his deputy.
  • September 2019: A report by HS2 Ltd chairman Allan Cook says the railway may not be completed until 2040, and the scheme could cost £88 billion.
  • January 2020: The Oakervee Review is widely leaked. It finds that HS2 could cost up to £106 billion, but concludes "on balance" that the project should continue.
  • December 2026: High-speed trains between London and Birmingham were due to begin running by this date, but HS2 Ltd admits this is "not viable".
  • 2027: Phase 2a from Birmingham to Crewe was due to open this year, but that is also subject to delay.
  • 2033: HS2 was due to be completed by this point, with Phase 2b running from Crewe to Manchester, and Birmingham to Leeds.