The HS2 committee responsible for hearing petitions against the rail project will today, July 9, hear challenges against the two main opposition groups - HS2 Action Alliance and Stop HS2.

MPs began the process of considering almost 2,000 petitions against £50bn HS2 last week but Government lawyers urged them to throw out 23 which they claimed did not meet official criteria.

That included petitions submitted by HS2 Action Alliance, a group with 15,000 individual members, and Stop HS2, a national organisation comprising 100 local factions.

Parliamentary rules state that petitions can only be made by groups or individuals "directly and specially affected by the project" – a definition the Government says cannot apply to national organisations.

The committee has already begun hearing the challenge to the locus standi - the right to be heard- of HS2 Action Alliance and is due to hear the Stop HS2 challenge at 2pm, to decide whether they can petition or not.

When it was announced that the two groups would be challenged, Stop HS2 Campaign Manager Joe Rukin said: "We are absolutely amazed that the Government wants to block us from giving evidence to the Hybrid Bill Committee.

"We work on behalf of over 100 action groups, yet HS2 Ltd are trying to claim that we do not represent anyone affected by HS2.

"I would have thought that as the HS2 Hybrid Bill Committee, like the Environmental Audit Committee and the HS2 Paving Bill Committee before them, approached us and asked us to appear before them as representatives of those affected by HS2, it has already been accepted that we represent those affected by HS2."

Mr Rukin said that Stop HS2 had already been listened to and agreed with by the committee on points made about hearing petitions from a sound expert early in the process and scrapping a secure email system.

"It’s pretty clear why HS2 Ltd and the Government don’t want us to give evidence, because we know what we are talking about and they have seen that Parliamentarians have listened to us in the past," he said.

Hilary Wharf, director of HS2 Action Alliance, said: "We’ve spent four years studying HS2 and have a very clear and practical set of recommendations that need to be considered.

"But of course if you know that what you are selling is fatally flawed you are tempted to resort to any action, democratic or not, to make sure that you force it through. It is sadly just further evidence that HS2 is all about politics rather than transport.”

"This is the last in a series of undemocratic actions from the Government as they try to force through the highly controversial line with the absolute minimum of public scrutiny," she said.

If the Government's argument is accepted it would mean both groups, as well as others whose locus standi is being challenged, could be barred from appearing before the High Speed Rail (London - West Midlands) Bill Select Committee.