A leading lobbying company has been secretly taped claiming to be able to directly influence David Cameron and other senior Government figures.
Executives from public affairs firm Bell Pottinger boasted to undercover reporters about their access to the Prime Minister, Chancellor George Osborne, Mr Cameron's policy chief Steve Hilton and Downing Street chief of staff Ed Llewellyn.
The claims by the Bureau of Investigative Journalism , published in The Independent, have been dismissed by Downing Street sources as "outrageous" and "a load of rubbish".
But Labour has insisted they are "very serious allegations" that demonstrate the need for lobbying reform.
Tim Collins, managing director of Bell Pottinger, told undercover reporters from the Bureau that he had worked with Mr Cameron and Mr Osborne in the Conservative Party's research department.
He also said Mr Llewellyn had worked under him at Conservative Central Office.
"I've been working with people like Steve Hilton, David Cameron, George Osborne for 20 years plus. There is not a problem getting the messages through," he said.
Mr Collins also claimed Bell Pottinger had got Mr Cameron to raise the matter of copyright infringement with Chinese premier Wen Jiabao on behalf of engineering firm Dyson.
"He [the Prime Minister] was doing it because we asked him to do it," Mr Collins claimed.
A Downing Street spokeswoman said: "Bell Pottinger nor any other lobbying firm has any say or influence over Government policy."
But shadow cabinet office minister Jon Trickett accused the Government of being "too close to corporate interests".
"These are very serious allegations involving a former member of the Conservative front bench as well as some of David Cameron's closest confidants inside Downing Street and his cheerleaders in the media," he said.
"We have been calling on the Government to implement a statutory register of lobbyists. We need reform to ensure that there is no question of the rich and powerful buying access to the Prime Minister and his advisers."