British Cabinet Secretary Sir Gus O’Donnell warned former Prime Minister Gordon Brown that a phone hacking inquiry would be open to legal challenge, documents released by the Cabinet Office reveal.
He also advised Mr Brown that launching a probe just two months before the General Election would “inevitably raise questions over the motivation and urgency of an inquiry”.
But officials insisted the final decision over whether an investigation should have been launched rested with the then Prime Minister.
A Cabinet Office spokesman said: “The advice, issued in March 2010, was based on the contents of the report of the Culture, Media and Sport Select Committee into Press Standards and other information available at the time.
“This advice was requested by the Prime Minister. Decisions on whether or not to hold a public inquiry, and on its scope and nature, are always the decisions of a minister.”