It included details which police were expected to reveal at a press conference later in the day: "It's not public yet that the two suspects in custody are 12 and 13". Mr Key was given talking points on the murder, including: "Our condolences go out to the family of the person killed", "Clearly this is a terrible tragedy", and "People will be shocked that the suspects are so young".
The briefing email warned Mr Key TV3 had been filming 11 UN diplomats and support staff given a free trip from New York to Queenstown - a potential source of embarrassment because the Government said it would not throw money at its bid for a UN Security Council seat.
Mr Key appeared to be told to downplay the visit by saying it was "focused on sustainable agriculture".
TV3 later revealed the UN group had been taken sightseeing, shopping and on a Shotover Jet ride.
The Prime Minister told reporters the cost of New Zealand's bid was dwarfed by the amount spent by Australia and other countries.
The briefing email suggested New Zealand had been caught unawares by Australian Prime Minister Tony Abbott's proposal to form an international coalition of centre-right Governments - including New Zealand - to oppose United States plans for stricter climate change policies.
Mr Key was advised to say: "I've not talked to Tony Abbott about this" and to emphasise New Zealand's record on climate change policies.
One of his talking points was: "This Government takes climate change seriously."
The briefing notes also warned Mr Key not to get involved in a battle between the Bay of Plenty Regional Council and community groups over whether the wreck of the Rena is to be left on Astrolabe Reef.
"It's ... likely to be a contentious decision ... and quite likely to be the subject of legal appeals, so essentially stay as far removed as possible from it," the notes said.
The briefing said journalists "appeared to be confused about the situation" and told him to clarify that the council had not yet agreed the Rena would stay on the reef.
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