The Foreign Office on Thursday urged Britons in the eastern Libyan city of Benghazi to leave, citing a "specific and imminent threat" to Westerners. Britain has warned its citizens against travelling to most parts of Libya since September, after an attack on the US consulate in Benghazi killed ambassador Christopher Stevens and three embassy staff, dpa reported. "We are aware of a specific, imminent threat to Westerners in Benghazi," the Foreign Office said. "We advise against all travel to Benghazi and urge any British nationals who are there against our advice to leave immediately."