Boris Johnson and Jeremy Hunt have both defended the freedom of the press after Scotland Yard threatened to prosecute anyone who reported the contents of leaked diplomatic cables.

As the row over the rights of the media intensified, the two Conservative leadership contenders united in condemning the suggestion that journalists could be pursued through the courts for reporting on leaked documents.

Scotland Yard said earlier it was investigating alleged “criminal breaches of the Official Secrets Act” following a leak which led to the resignation of Britain’s ambassador to Washington, Sir Kim Darroch this week.

Announcing how counter terrorism police had begun an investigation into the leak of diplomatic cables, Assistant Commissioner Neil Basu took the unusual step of warning newspapers and social media users that they would be committing a criminal offence by publishing further secrets.

With-in hours, the former Chancellor George Osborne condemned his comments as "very stupid and ill-advised" before urging Cressida Dick, the Met Commissioner, that her constabulary was in a "mess" and unless she officially overruled Mr Basu there "will be calls for resignations".