Shadow transport secretary Mary Creagh has said that Labour supports the HS2 plan as it will address the need for more rail capacity across the country.
She said: "Labour supports HS2 because we must address the capacity problems that mean thousands of commuters face cramped, miserable journeys into Birmingham, Manchester, Leeds and London.
"However, three years of Government delays and mismanagement has caused costs to balloon. Incompetent ministers have only just launched the consultation on phase 2 of the route, despite the fact that it was being worked on when Labour were in government."
Virgin Trains has had an application to run extra services on the busy West Coast Main Line turned down by rail regulators.
Virgin wanted to operate additional services to Blackpool and Shrewsbury.
But the Office of Rail Regulation said it had decided at this stage not to grant track access, saying there was not enough space on the line to run all the extra services.
The ORR added: "The proposals would have also caused further deterioration in punctuality by adding traffic to what is already a very busy route, on which Network Rail (NR) is currently not meeting the punctuality targets it has been funded to deliver.
"The proposals would have a detrimental impact on the journeys of millions of passengers travelling on the route."
ORR chief executive Richard Price said: "We understand that many people will be disappointed that ORR cannot at this stage give the go-ahead for new direct train services from London to Blackpool and Shrewsbury.
"We recognise the public support for these proposals, however our analysis shows the introduction of new services would see performance deteriorate on this key route for passengers.
"Although we are unable to grant access right now, we are putting pressure on NR both to improve its performance and to carry out improvements on the WCML so that the question of new services from London to Blackpool and Shrewsbury can be looked at again as soon as possible."
Transport Secretary Patrick McLoughlin has said that those who need to sell their house but struggle because of the HS2 plans will still be helped and that he wants the line, "to create jobs and prosperity not to harm it."
"I understand how proposals like this can affect the property markets so compensation will be as generous as on the first phase, and more generous then when we built the motorways."
The Prime Minister says the money to pay for HS2 will need to come from 'a balance' between the Government and 'the train user' - but expensive tickets are necessary for 'Britain to be a success'. See the full interview above.
David Cameron was resolute when asked about Tory opposition to the HS2 project: "This is going to happen. I have been a strong supporter right from the start." The Prime Minister continued:
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.
Unprecedented growth in the last ten years has seen passenger journeys grow by 50 per cent to almost 1.5bn a year and that number is set to continue to grow. More people use the railways today than at any time since the Second World War, on a network half the size it was then ...
This is a rare chance to stop playing catch-up on capacity.
– David Higgins, chief executive, network rail
He added that Network Rail was already planning to ensure that HS2 would integrate with the existing network with as little disruption as possible.