Foreign Secretary William Hague ordered the expulsion of two more Libyan diplomats from the UK today in a attempt to ratchet up the pressure on the Gaddafi regime.
Mr Hague said they had been engaged in activities "contrary to the interests of the UK", giving them and their families until May 11 to leave the country.
The move follows the expulsion of the Libyan ambassador to London in retaliation for the destruction of the British embassy in Tripoli by a mob.
"I ordered the expulsion of the two diplomats on the basis that their activities were contrary to the interests of the UK," he said in a statement.
"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."
The Foreign Office would not give details of the alleged behaviour which led to the expulsions but said it had not posed any immediate threat to UK security.
It is thought they are accused of activities similar to those that led to five of their colleagues being thrown out of the UK in March, including intimidating opposition figures.
Mr Hague, attending a meeting of the international contact group on Libya in Rome, welcomed a commitment to "intensify the pressure on the regime politically, militarily and economically".
"The tempo of the military action should continue to be increased as it has been increasing in recent days," he said.
The contact group also agreed to establish a temporary funding mechanism to channel support to the rebel administration in Benghazi.
The Transitional National Council has said that it needs two to three billion dollars in the coming months in order to pay military salaries and to bring in food, medicines, and other essential supplies.
Downing Street has however said that the UK did not intend at present to contribute, having already made "a very substantial contribution" to humanitarian assistance in the country.
Meanwhile the Ministry of Defence disclosed that a Royal Navy minehunter had destroyed a mine laid by pro-Gaddafi forces in waters off the besieged rebel-held port of Misrata.
HMS Brocklesby used sonar and the Seafox underwater disposal system to locate and destroy the device containing more than 100 kilograms of high explosive which had been placed just a mile from the harbour entrance.
It was said to have been taken there by regime forces using an inflatable dinghy as part of their attempts to choke off the flow of humanitarian assistance and evacuation efforts.
Lieutenant Commander James Byron, the commanding officer of HMS Brocklesby, said: "In helping to keep the port of Misrata open we are ensuring the continued flow of essential medical assistance and allowing the evacuation of innocent civilians from the country."
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