Elizabeth Filkin, the former parliamentary commissioner for standards, warned the police force of drinking with reporters as she outlined a new framework for officers coming into contact with journalists. She described it as a “fraught issue”.

In a guide issued at Scotland Yard, officers will be encouraged to keep records of any conversations they have with a member of the press.

Filkin, who undertook a review press-police relations as a result of of the phone-hacking inquiry,  said it was many people from all walks of British society thought that “information is deliberately leaked for various kinds of improper benefits”.

She said there were “some very serious issues” relating to contact between journalists and police  which “eroded trust from the public”.

She said drinking with officers “may be seen as inappropriate hospitality”, adding: “Mixing the media with alcohol is not banned but should be an uncommon event.”

The report urges officers to “watch out” for “late-night carousing, long sessions, yet another bottle of wine at lunch – there are all long-standing media tactics to get you to spill the beans. Avoid.”

Met Police Commissioner Bernard Hogan-Howe welcomed the report, adding: “We need to be open about our contact with the media.”

Mr Hogan-Howe said the era of “secret conversations and improper contact” between police and the media was over.