Libya Business News sources have confirmed that all non-essential staff have been evacuated from the British embassy in Tripoli.
The precise reason for the move is unclear, but it follows similar action from other embassies in the city, as armed militias focus their attention on government ministries.
Adding to the disquiet in Tripoli is the apparent sophistication of the bomb used in the recent attack on the French embassy; evidence that a skilled bomb-maker has set up shop in the capital have led to increased security measures and fears of further attacks.
On Wednesday, a joint statement from US, UK and France said that the democratically elected representatives and leaders of the Libyan people must be able to carry out their duties motivated by their responsibility to the Libyans who elected them, rather than by the threat of force.
It added that "the international community is observing the country with concern".