Plans to build a super-fast rail network in the UK in the next few decades might not be as feasible as it was first thought. 

The Major Projects Authority has given the High Speed 2 (HS2) project an amber/red warning in its annual report, which has raised concerns the ambitious development may not get off the ground.

According to the Department for Transport (DfT), this rating is based on information from June 2012 and significant progress has been made in the 11 months since.

However, Stop HS2 - a lobby group that is against the multi-billion pound train line - believes this is not the case.

Indeed, the campaigners labelled the project a "white elephant" and said the DfT and transport secretary Patrick McLoughlin would be rushing to publish updated information if it was available.

Although the government believes the fast trains will bring untold economic benefits, a number of local councils have questioned the decision to spend so much money on the lines between London, Birmingham, Manchester and Leeds.