"I ordered the expulsion of the two diplomats on the basis that their activities were contrary to the interests of the UK," Hague said in a statement, adding that he made the order on Wednesday.
"They and their dependants now have until May 11 to leave the country.
"We keep the status of the Libyan embassy and its staff under constant review. I judged that the behaviour of these individuals had become unacceptable, and that they should therefore be declared persona non grata."
Omar Jelban, the Libyan ambassador, left Britain on Monday, the day after Hague announced his expulsion following attacks on the British embassy in Tripoli.
London blamed Moamer Kadhafi's regime for failing to protect the empty building.
Britain has had no diplomatic representation in Tripoli since the start of hostilities in the country, although a Foreign Office team is based in the rebel-held city of Benghazi.
Britain is at the forefront of the international bombing campaign against Libya, carried out under a UN Security Council resolution to protect civilians from fierce fighting between Kadhafi's forces and rebels against his rule.
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