A Metropolitan Police team is to fly to Libya to continue the investigation into the murder of Wpc Yvonne Fletcher, the Prime Minister has announced.
David Cameron said the visit was a "really positive step forward" in the inquiry into the 1984 killing of the officer, who was shot dead as she policed an anti-Gaddafi demonstration outside the Libyan People's Bureau in London.
He was speaking as the north African state's interim prime minister Abdurrahim El-Keib visited 10 Downing Street.
Mr El-Keib promised that his country would "work very closely together" with the UK to resolve outstanding questions about the killing of 25-year-old Wpc Fletcher, who is believed to have been hit by a shot fired from within the People's Bureau.
Her death led to an 11-day siege of the building in St James's Square and the severing of diplomatic links between the UK and Libya. Mr El-Keib worked with the opposition while in exile during Muammar Gaddafi's dictatorship and said he knew some of those involved in the demonstration.
He told Mr Cameron: "The Fletcher case is a case that is close to my heart personally. I had friends who were demonstrating that day next to the embassy.
"It is a sad story. It is very unfortunate that it has anything to do with the Libyan people. I am here to tell you that we will work very closely together to resolve anything related to that issue."
Hopes of finding the killer of Wpc Fletcher were raised following the revolution which toppled Gaddafi last year.
But so far, plans to send a police team to Libya have been frustrated by a failure to secure approval from local authorities.