Lobbyists want more transparency in their profession to avoid being “tarnished by a never-ending string of scandals”, the lobbying industry body has said.

A survey carried out on behalf of the Chartered Institute of Public Relations (CIPR) found overwhelming support for more transparency for who is lobbying Westminster politicians and a widespread belief that recent lobbying scandals have diminished public trust in politics.

The body pointed to scandals such as the Greensill affair, in which the now Foreign Secretary Lord Cameron was found to have been lobbying for disgraced financier Lex Greensill, and recent allegations that Conservative MP Scott Benton had breached Commons rules on lobbying as evidence that current regulation was not fit for purpose.

The CIPR’s survey also found a quarter of lobbyists thought the Lobbying Act, passed in 2014, had made no difference to transparency, while another third thought it had only improved transparency a little.

Rachael Clamp, president of the CIPR, said: “It was clear 10 years ago that the Lobbying Act wasn’t fit for purpose, and the poll results show this is evidently still the case. The Act contains so many loopholes and exemptions that the vast majority of lobbying is out of scope.”

The poll, which surveyed 235 lobbyists and PR professionals, found 86% thought there should be greater transparency in Westminster lobbying and 88% saying lobbying scandals had affected public faith in politics.

Ms Clamp added: “Lobbying is a force for good and has brought about a huge amount of progressive change throughout the course of history, though its good name is being tarnished by a never-ending string of scandals made possible by the defective Act. This poll finds UK lobbyists speaking with one voice when they call for greater transparency to restore confidence in this vital element of the democratic process.

“As the election looms closer, there is a risk that lobbying reform is squeezed out of manifestos. This would be a mistake. Prospective parliamentary candidates might think that lobbying isn’t a typical doorstep issue, but it is one that sits at the heart of voters’ perception of MPs, and is exactly the kind of issue that will determine whether the door is even opened.”

The CIPR has previously called for reform of lobbying rules and for the register of lobbyists to be expanded to cover the whole sector as part of its “Lobbying for Good Lobbying” campaign.