British police accidentally let slip their plans to arrest Julian Assange should he leave the Ecuadoran embassy in London, with pictures of their notes appearing in newspapers on Saturday.
A policeman outside the embassy was photographed carrying a handwritten document marked "restricted" and "decision - supporting rationale".
It said the WikiLeaks founder was to be arrested "under all circumstances" should he step outside the embassy, which is situated in a mansion block next to the luxury Harrods department store, in the plush Knightsbridge district.
The document suggested that if the 41-year-old Australian attempted to leave the embassy in a vehicle, under diplomatic immunity or in a diplomatic bag, then he should be arrested.
"The document is one officer's notes from a briefing," a Scotland Yard spokesman said.
"Our objective is to arrest Julian Assange for breach of bail. Under no circumstances would any arrest be made which was in breach of diplomatic immunity."
Assange, having exhausted all his legal options in Britain to avoid extradition to Sweden - where he is wanted for questioning over sex crime allegations - walked into the Ecuadoran embassy on June 19 and claimed asylum. Quito has granted the request.
Assange fears he would be passed on to the United States, which he enraged by releasing a vast cache of its confidential government files.
Britain says it is legally obliged to extradite him to fellow European Union member Sweden, should he leave the embassy.
The police document reads: "EQ embassy brief - summary of current position re Assange.
"Action required -- Assange to be arrested under all circumstances.
"He comes out with dip. immun., as dip. bag. in dip. bag (right to life) in dip. vehicle - ARRESTED."
The document also warns of the "possibility of distraction", suggesting police fear that his supporters might try to cause a commotion, providing Assange with enough cover to leave.
The Organization of American States declared "solidarity and support" Friday for Ecuador in its position over Assange.
The meeting was convened at Ecuador's request to consider a resolution rejecting any attempt to put at risk the "inviolability" of its London embassy.
In the resolution, the 34-member regional body rejected "any attempt that might put at risk the inviolability of the premises of diplomatic missions."