How Milly Dowler’s voicemails were deleted is “not the prime issue” the editor of the Guardian, the paper that broke the phone hacking story, told the Leveson Inquiry.

The deletion of the voicemails, three days after the schoolgirl went missing in 2002, gave false hope to Dowler’s parents and led to an outpouring of scorn that ultimately forced the closure of the News of the World.

However, in December, Scotland Yard released a statement indicating that it was unlikely that a journalist from News International erased Dowler’s messages, prompting a storm of criticism to be levelled at the Guardian, particularly from former News of the World employees.

Taking the stand at the Leveson Inquiry, Guardian editor Alan Rusbridger said that the deletion of Milly Dowler's voicemails was not the explanation given for closing the Sunday tabloid.

He told the Inquiry: "To some extent it's a siding. I think there were people who are trying to elevate this [the deletion of Milly Dowler's voicemails] into a primary issue now who didn't think that it was at the time.

"I think when you trace back the reasons that were given for the closure of the News of the World at the time, they certainly weren't that."

Mr Rusbridger said establishing how Milly's voicemails were deleted was "not a simple question", as shown by the length of time it is taking to investigate the matter.

The Guardian and the Metropolitan Police have carried out reviews looking at what happened to the schoolgirl's phone messages.

Lord Justice Leveson has said he intends to make the results of these inquiries public, although some details will have to be blanked out.

Earlier on Tuesday, Private Eye Editor Ian Hislop questioned the “cosy” relationship enjoyed by News International and Britain’s top political class.