MPs have a "duty" to make the Palace of Westminster available to visitors whilst ensuring that the cost of doing so does not fall to the taxpayer, the chairman of the Finance and Services Committee has said.
Liberal Democrat John Thurso said the cost should be recovered from those visitors, during a debate on the medium-term financial plan for the Commons administration and savings programme on 8 November 2012.
Mr Thurso stressed that it was important there was "no conflict between Parliament as a working institution and the Palace as a world class visitor attraction".
However, Robert Halfon, the Conservative MP for Harlow, was worried the move would hand the wealthy special access to Parliament.
"It will mean that people who are rich when they are corporates who can pay more money, will have special privileges to get into the House of Westminster," he said - a situation which he found "objectionable".
He also feared it would create a "dangerous precedent".
"Once you allow the precedent, where do we stop? Do we then have rollercoasters outside?
"You may laugh at this, but once you agree the principle that we become nothing more than a theme park, you create a dangerous precedent."
Sir Alan Haselhurst, a former deputy speaker, said Mr Halfon had a "very vivid imagination", telling him: "It really does not help the quality of the debate to start using terms like theme park."
Sir Alan said he thought the Palace of Westminster could be made more accessible to the public.
Shadow Commons leader Angela Eagle said Labour was "broadly supportive" of the Commission's proposals, which set out plans in 2010 to make savings of 17% by 2014.
But she cautioned that any savings must not affect the ability of MPs to carry out their parliamentary functions.
"This building isn't here to sell afternoon tea and guided tours, it is a working Parliament," she said.
Mr Halfon later called a vote on his amendment, which would give MPs a specific vote on the "increased commercialisation" of Parliament, but this was rejected by 179 votes to 13, a government majority of 166.
The main motion was then approved without a vote.