Today's statement from the British, US and Libyan governments follows an interview ITV News did earlier this week with the justice minister from Libya, in which he said he was now willing to cooperate with police in the US and UK.
The Foreign Office has now welcomed that development and said that it looks forward to visiting Libya in the new year and to getting access to information and witnesses to progress their investigation.
Scotland's Lord Advocate has previously said there are still people out there with blood on their hands for this atrocity.
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TV presenter Alice Beer has said the pair received similar kidnap and rape threats just weeks before the Crimewatch star was murdered.
In an interview with The Sunday Telegraph David Cameron has set out a series of policies designed to appeal to traditional Tory voters.
Nick Clegg will attempt to win over the female electorate when he kicks off the Liberal Democrats' general election campaign later today.