A key parliamentary committee backed the government's plans to build a £32 billion high-speed rail network on Tuesday, saying the project would dramatically improve transport links and could bring big economic benefits.

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 Prime Minister David Cameron's Conservative Party -- who worry about the impact on their homes and the countryside.

Parliament's Transport Committee, which includes politicians from all the main parties, concluded after an inquiry that there was a good case for a high-speed rail network and broadly supported the government's plans.

A high-speed line offers potential economic and strategic benefits which a conventional line does not, including a dramatic improvement in connectivity between our major cities, (London's) Heathrow and other airports, and the rest of Europe, said committee chair Louise Ellman.

Britain's coalition government is slashing public spending over the next four years to rein in a big budget deficit.

But Ellman, from the opposition Labour Party, said the high-speed rail project, entailing spending of around 2 billion pounds a year over 17 years, was affordable.

High speed rail may be a catalyst for economic growth, helping to rebalance the economy and bridge the north-south divide, she said, referring to the income gap between the north of England and the more prosperous south.

However, she voiced concern that, under current plans, high-speed rail lines will not reach the northern cities of Manchester and Leeds for more than 20 years.

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.

A public consultation on the project ended in July and the government is due to announce its final decision on high-speed rail before the end of the year.

Britain lags far behind many Asian and European countries in high-speed rail. It has only about 110 km of high-speed line, linking London to mainland Europe via the Channel Tunnel.

(Reporting by Adrian Croft; Editing by Steve Addison)