The government has postponed until January a decision on building a new 32 billion pound high-speed rail network so as to consider measures to reduce the impact on those living nearby and the environment, media reported on Saturday.

A decision had been expected by the end of the year, but the media reports said the decision had been delayed to consider the construction of a 500 million pound tunnel to reduce the proposed network's environmental impact.

The important thing is to make the right decision, even if that means a delay of a few parliamentary days, a Department for Transport spokeswoman said.

She confirmed the tunnel proposal but dismissed as speculation reports of its cost.

The proposed 400 km per hour line connecting London with major cities to the north has run into angry opposition from people living near the route -- many of them supporters of David Cameron's Conservative Party worried about the impact on their homes and the countryside.

The government's proposal is for a new Y-shaped high-speed rail network. The initial phase would connect London and Birmingham by 2026, reducing journey times to 49 minutes from 84. Lines to Manchester and Leeds would open by 2033.

(Reporting by Mohammed Abbas; Editing by Ralph Gowling)