The two codes of conduct are identical, except for the addition of a 22nd clause in the Coalition code, which states that staff must: "Other than in the course of their professional duties, not post personal online commentary or other material or publish books or articles expressing personal views which relate to either their minister's portfolio area or the general work of the Australian government."

"The Prime Minister's chief of staff should be consulted for further guidance."

Though staff have not been banned from using Twitter, Facebook or other social media sites, the move is designed to head off potentially embarrassing commentary for the government.

The move comes after the Prime Minister's office last year cracked down on media appearances by the Coalition frontbench, issuing an edict that all media requests for interviews be approved by the Prime Minister's staff.

Government insiders dismissed suggestions the move was a "command and control" measure and described it as an attempt to prevent Coalition staff developing high public profiles, as occurred during the Rudd and Gillard governments.