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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Kate will join Prince William on a tour of the Stephen Lawrence Centre before visiting a charity working with disadvantaged young people.
There is an "urgent need" for a "simpler and more trusted" system for investigating clinical failures, according to a damning report.
Over 100 mothers and fathers were investigated for leaving their children unsupervised in the final three months of 2014, new figures find.