THE decision not to publish a key report into HS2 will be re-examined by the courts.

A Judicial Review into the government's decision to withhold the publication of a critical report from the Major Projects Authority will now take place after Mr Justice Singh made the ruling at London's High Court on Monday.

The report rated the controversial HS2 project as being amber-red, meaning there are serious doubts as to the viability of the scheme.

The Information Commissioner said in May 2012 the report's contents should be made public, and their appeal to the courts for a Judicial Review has now been granted.

Transport Secretary Patrick McLoughlin last year used a rarely-used power of veto to block publication of the MPA report and the courts will now investigate if that decision was lawful.