Fast Turnaround

During the undercover meeting, Bell Pottinger – whose chairman is Margaret Thatcher’s former media adviser Lord (Tim) Bell – claimed to have used its influence on behalf of the engineering firm Dyson to ask Mr Cameron to complain about copyright infringement to the Chinese premier Wen Jiabao during a state visit in June 2011.

"We were rung up at 2.30 on a Friday afternoon, by one of our clients, Dyson," Mr Collins explained. "He said 'We’ve got a huge issue and that is that a lot of our products are being ripped off in China' … On the Saturday David Cameron raised it with the Chinese prime minister."

He added that, "He [Cameron] was doing it because we asked him to do it," and because the issue was in the wider national interest.

"In terms of very fast turnaround and getting things done right at the top of government if you’ve got the right message yes we can do it," he said.

Mr Collins also recommended a meeting with Daniel Finkelstein, the Times chief leader writer – who he said was very close to Mr Cameron.

"He will sit down and have lunch with just about anybody," he said. "That doesn’t mean he’s going to agree with them… but occasionally something out of that lunch or dinner will get dropped into a future column."

Joint events could be held with influential think-tanks close to government, such as Policy Exchange, the firm suggested. Another strategy would include passing information to key academics "so that they are then blogging the right messages out there, so it’s actually coming from an independent," said Mr Wilson.

Mr Finkelstein said: "I am flattered if anyone thinks I am interesting enough to have lunch with. But anyone promoting either undemocratic or anti-social policies would find me a pretty closed door and hasn’t to my knowledge come knocking."

Discussing techniques for managing reputations on-line, Mr Wilson mentioned a team that could "sort" Wikipedia.

"We’ve got all sorts of dark arts," added Mr Collins. "I told [David Wilson] he couldn’t put them in the written presentation because it’s embarrassing if it gets out, because he’s so good at it."