Labour MP Paul Flynn has described lobbyists as "professional persuaders and professional deceivers", during a Westminster Hall debate on parliamentary lobbying on 2 November 2011.
He spoke out against "rich, corporate lobbying" and urged fellow MPs to "take a puritanical line", registering all dealings they have had with lobbyists.
Concerns have been raised that there is undue influence by lobbyists on government policy, and legislation for a statutory register of lobbyists is due to be introduced in 2012.
Political Reform Minister Mark Harper confirmed that proposals for the consultation on the register would start by the end of November.
However he said that legislation "mustn't stifle lobbying and stop people talking to us".
All MPs, including ministers, are subject to a code of conduct when it comes to their outside interests and dealings.