A leaked report warns HS2 could cost up to £106 billion.
Here are nine key questions about the high-speed rail project.
– What was its original expected cost?
The project was allocated £56 billion in 2015.
– What is the latest estimate?
A widely leaked review by Douglas Oakervee found it could cost up to £106 billion.
– How much money has already been spent?
HS2 Ltd has spent around £8 billion. The money has gone towards the purchase of land and property, ground investigation work, technical designs, IT systems, wages and public engagement.
-Who is in favour of HS2?
Political leaders in northern England and business groups claim the railway is vital to boosting transport links across the region, providing increased capacity on an overcrowded network.
Construction firms warn that scrapping HS2 would cause major damage to the industry.
-Who are its opponents?
Several environmental groups claim building HS2 would cause huge damage to natural habitats, including dozens of ancient woodlands.
Communities living on or near the route have expressed anger at the impact on their lives, while many people have said the project is simply too expensive and the money would be better spent elsewhere.
– What is the planned route?
Phase 1 is planned to run between London and Birmingham.
Current designs involve a second Y-shaped phase launching in two stages: Phase 2a from the West Midlands to Crewe followed by phase 2b from Crewe to Manchester, and Birmingham to Leeds.
– When is it due to open?
The first phase was due to open in 2026, but a recent report by HS2 Ltd stated this could be pushed back until 2031.
– What impact would HS2 have on journey times?
Examples given by HS2 Ltd include Manchester-London journey times cut from two hours and seven minutes to one hour and seven minutes, and Birmingham-London trips reduced from one hour and 22 minutes to 45 minutes.
– When will a decision be made?
Transport Secretary Grant Shapps said the Government will make an announcement in “weeks rather than months”.