Benghazi was the stronghold of the Western-backed revolt that eventually ended Gaddafi's hold on power in Libya.
However, Britain has not had any diplomatic presence in the city since an attack on the US mission last September that killed American ambassador Chris Stevens and three of his colleagues.
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The British public have voted St Paul's Cathedral the country's favourite building ahead of Stonehenge and Buckingham Palace.
A service to remember 'Operation Dynamo', the code name for the mass evacuation of allied troops in 1940, will take place on the beach.
The Bank of England has launched a secret project looking at the economic risk to Britain if the country votes to leave the European Union.