David Cameron has insisted new high-speed rails links to the north of England will go ahead despite a backlash as the routes were unveiled.
The Prime Minister said extending the already-planned London to Birmingham HS2 line as far as Manchester and Leeds would "spread wealth and prosperity" around the country.
But some Conservative backbenchers have attacked the announcement and warned they would not support "flawed" government policy.
The Stop HS2 campaign has also challenged claims that the extended rail links will be good for the economies of the Midlands and the North.
Ministers are also braced for fierce opposition to the plans from rural communities in areas affected by the plans.
But Mr Cameron told Sky News: "You have to plan for these things. High Speed 1, linking us to the Channel Tunnel was a long time in planning but it is good to get on with this now.
"And, yes, these are difficult economic times, but I think that is precisely the time you should be planning for the future, working out how we link up the cities of our country, how we reduce journey times, how we spread wealth and prosperity around the country.
"We do need to rebalance the economy, it has been too dominated by the south and by certain industries and high-speed rail will really help to create a better balanced economy."
Pressed on whether Tory opponents could force him into a U-turn, Mr Cameron insisted the scheme would go ahead.
"This is going to happen. I have been a strong supporter right from the start, in Opposition."
https://www.gov.uk/government/organisations/department-for-transport(Department for Transport)