Westminster HS2 rail link protest
Campaigners against a proposed high speed rail link are taking their arguments to Westminster.
Stop HS2 is taking part in Monday's lobby organised by south Northamptonshire MP Andrea Leadsom.
Convener Joe Rukin said he could not understand why the government was still consulting on the scheme when cuts were being made elsewhere.
The planned new 250mph rail route between London and Birmingham aims to cut the journey time to 49 minutes.
The government has also said it would back high-speed link plans from Birmingham to Manchester and Leeds.
However, opponents say the move would be bad for the environment and cost more than could be afforded.
"It is amazing that the government are still willing to go ahead with this when everything else has been cut," Mr Rukin said.
Plans for the new rail link were announced under the previous government in March.
It was backed in the coalition deal between the Conservatives and the Liberal Democrats but they have said no final decision will be taken until a full public consultation, due to start in 2011, has been carried out.