A DECISION on the proposed high-speed rail line to the edge of Liverpool has been delayed – but ministers refused to confirm it was to allow a £500m tunnel to be drilled, heading off a Cabinet revolt.

The one-month hold-up will allow Transport Secretary Justine Greening to give "detailed and careful consideration to the issues raised in the recent public consultation", MPs were told.

But the statement made no reference to newspaper leaks revealing the Government is preparing to spend an extra £500m on a short tunnel in the constituency of Welsh Secretary Cheryl Gillan.

The surprise move – over-ruling the recommendation of expert engineers who devised the route – would bury 1.5 miles of the track under the beautiful Chiltern Hills, in Buckinghamshire.

Ms Gillan had threatened to resign if the £32bn high-speed rail (HS2) project went ahead as planned through her Chesham and Amersham constituency – and many other Tory MPs are in revolt.

However, supporters of HS2 – to build a 250mph line from London to Birmingham, then on to Manchester and Leeds – believe the hold-up has set a dangerous precedent that could kill the flagship project.

They fear the show of government weakness will encourage other MPs to demand a tunnel in their constituencies, triggering further delays and legal actions.