Wikileaks founder Julian Assange has expressed "shock" after new documents revealed fresh details about the involvement of UK authorities in his long-running battle to avoid extradition to Sweden.
He has been living inside the Ecuadorian embassy in London for more than three years, fearing he will be taken to the United States if he travels to Sweden, where he faces sex allegations - which he has always denied.
Assange has offered to be interviewed inside the embassy, but attempts to set up a meeting with Swedish prosecutors have foundered.
He believes the United States authorities want to quiz him about the activities of WikiLeaks.
Emails obtained by Italian news magazine L'Espresso under the Freedom of Information Act showed that Britain's Crown Prosecution Service wrote to the Swedish authorities in 2011, saying it would "not be prudent" for them to interview Assange in the UK.
"Any attempt to interview him under strict Swedish law would invariably be fraught with problems," said one email, dated January 25, 2011.
Another email dated January 13, 2011 said: "Please do not think that the case is being dealt with as just another extradition request."
Assange said: "This is astonishing. I have been on the phone with my lawyers all morning and they are as shocked as I am."
L'Espresso said Britain rejected its FoI requests, but the Swedish authorities released 226 pages of documents.
The magazine said the files revealed that, from the very beginning, the CPS in London advised the Swedish prosecutors against an investigative strategy it said could have led to a quick closure of the preliminary investigation into the case.
Assange's supporters believe the emails are "hugely significant" because they "set the narrative" from the start of the Swedish investigation.
It was being suggested that the CPS was "manipulating" the process in the extradition case, with calls for the CPS and the Home Office to offer explanations about the emails.
A legal source at WikiLeaks said it was looking into all options.
The January 2011 email from an official at the CPS to the Swedish prosecutors said: "My earlier advice remains, that in my view it would not be prudent for the Swedish authorities to try to interview the defendant in the UK."
The email was dated a week before an extradition hearing started in the UK, so WikiLeaks believes it was clear advice was already being given by the CPS.
The email continued: "Even if the defendant was to consent to such an interview (by appointment) on a mutually agreed basis, the defence would without doubt seek to turn the event to its advantage."
In another email from the CPS to the Swedish prosecutor Marianne Ny, dated November 2012, reference is made to a "ghastly Swedish journalist" seeking information, adding: "Suffice it to say none of the team will under any circumstances correspond/speak with her."
The email finishes: "I am sure you can guess what I would just love to send to you as a Christmas present."
Another email in the same month says: "There is no question of him being allowed out of the Ecuadorian embassy, treated and then allowed to go back. He would be arrested as soon as was appropriate."
It is not clear if Assange had requested to leave to have medical treatment in 2012.
It was recently revealed that his doctor had asked for Assange to be given safe passage from the embassy to have an injured shoulder examined.
The Metropolitan Police removed a 24-hour guard on the Ecuadorian embassy earlier this month, which had cost an estimated £12 million.
A CPS spokesperson said: "In 2011, when this advice was given, extradition proceedings were under way. We were following due process and advice was being given to facilitate that request. We could not have anticipated later developments and in particular that Mr Assange would fail to surrender when the courts ordered his extradition to Sweden.
"An interview of Mr Assange was not necessary for the extradition request to succeed.
"The Swedish Authorities were and remain ready to prosecute Mr Assange should he decide to leave the Ecuadorean Embassy in order to face due process.
"Mr Assange and his legal advisers had ample opportunity to raise all their objections to the extradition both in the UK courts and in Europe. It follows that the delay here is entirely due to Assange's failure to surrender."